1
|
Elziny S, Sran S, Yoon H, Corrigan RR, Page J, Ringland A, Lanier A, Lapidus S, Foreman J, Heinzen EL, Iffland P, Crino PB, Bedrosian TA. Loss of Slc35a2 alters development of the mouse cerebral cortex. Neurosci Lett 2024; 836:137881. [PMID: 38909838 DOI: 10.1016/j.neulet.2024.137881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 06/17/2024] [Accepted: 06/19/2024] [Indexed: 06/25/2024]
Abstract
Brain somatic variants in SLC35A2, an intracellular UDP-galactose transporter, are commonly identified mutations associated with drug-resistant neocortical epilepsy and developmental brain malformations, including focal cortical dysplasia type I and mild malformation of cortical development with oligodendroglial hyperplasia in epilepsy (MOGHE). However, the causal effects of altered SLC35A2 function on cortical development remain untested. We hypothesized that focal Slc35a2 knockout (KO) or knockdown (KD) in the developing mouse cortex would disrupt cortical development and change network excitability. Through two independent studies, we used in utero electroporation (IUE) to introduce CRISPR/Cas9/targeted guide RNAs or short-hairpin RNAs into the embryonic mouse brain at day 14.5-15.5 to achieve Slc35a2 KO or KD, respectively, from neural precursor cells. Slc35a2 KO or KD caused disrupted radial migration of electroporated neurons evidenced by heterotopic cells located in lower cortical layers and in the sub-cortical white matter. Slc35a2 KO in neurons did not induce changes in oligodendrocyte number, importantly suggesting that the oligodendroglial hyperplasia observed in MOGHE originates from distinct cell autonomous effects of Slc35a2 mutations. Adult KO mice were implanted with EEG electrodes for 72-hour continuous recording. Spontaneous seizures were not observed in focal Slc35a2 KO mice, but there was reduced seizure threshold following pentylenetetrazol injection. Here we demonstrate that focal Slc35a2 KO or KD in vivo disrupts corticogenesis through altered neuronal migration and that KO leads to reduced seizure threshold. Together these results demonstrate a direct causal role for SLC35A2 in cortical development.
Collapse
Affiliation(s)
- Soad Elziny
- Dept. of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Sahibjot Sran
- Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH, United States
| | - Hyojung Yoon
- Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH, United States
| | - Rachel R Corrigan
- Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH, United States
| | - John Page
- Dept. of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Amanda Ringland
- Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH, United States
| | - Anna Lanier
- Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH, United States
| | - Sara Lapidus
- Dept. of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - James Foreman
- Dept. of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Erin L Heinzen
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy and Department of Genetics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Philip Iffland
- Dept. of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Peter B Crino
- Dept. of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Tracy A Bedrosian
- Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH, United States; Dept. of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, United States.
| |
Collapse
|
2
|
Bernardo P, Cuccurullo C, Rubino M, De Vita G, Terrone G, Bilo L, Coppola A. X-Linked Epilepsies: A Narrative Review. Int J Mol Sci 2024; 25:4110. [PMID: 38612920 PMCID: PMC11012983 DOI: 10.3390/ijms25074110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/03/2024] [Accepted: 04/06/2024] [Indexed: 04/14/2024] Open
Abstract
X-linked epilepsies are a heterogeneous group of epileptic conditions, which often overlap with X-linked intellectual disability. To date, various X-linked genes responsible for epilepsy syndromes and/or developmental and epileptic encephalopathies have been recognized. The electro-clinical phenotype is well described for some genes in which epilepsy represents the core symptom, while less phenotypic details have been reported for other recently identified genes. In this review, we comprehensively describe the main features of both X-linked epileptic syndromes thoroughly characterized to date (PCDH19-related DEE, CDKL5-related DEE, MECP2-related disorders), forms of epilepsy related to X-linked neuronal migration disorders (e.g., ARX, DCX, FLNA) and DEEs associated with recently recognized genes (e.g., SLC9A6, SLC35A2, SYN1, ARHGEF9, ATP6AP2, IQSEC2, NEXMIF, PIGA, ALG13, FGF13, GRIA3, SMC1A). It is often difficult to suspect an X-linked mode of transmission in an epilepsy syndrome. Indeed, different models of X-linked inheritance and modifying factors, including epigenetic regulation and X-chromosome inactivation in females, may further complicate genotype-phenotype correlations. The purpose of this work is to provide an extensive and updated narrative review of X-linked epilepsies. This review could support clinicians in the genetic diagnosis and treatment of patients with epilepsy featuring X-linked inheritance.
Collapse
Affiliation(s)
- Pia Bernardo
- Pediatric Psychiatry and Neurology Unit, Department of Neurosciences, Santobono-Pausilipon Children’s Hospital, 80129 Naples, Italy
| | - Claudia Cuccurullo
- Neurology and Stroke Unit, Ospedale del Mare Hospital, ASL Napoli 1 Centro, 80147 Naples, Italy;
| | - Marica Rubino
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University Federico II of Naples, 80131 Naples, Italy (L.B.)
| | - Gabriella De Vita
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, 80131 Naples, Italy;
| | - Gaetano Terrone
- Child Neuropsychiatry Units, Department of Translational Medical Sciences, University Federico II of Naples, 80131 Naples, Italy;
| | - Leonilda Bilo
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University Federico II of Naples, 80131 Naples, Italy (L.B.)
| | - Antonietta Coppola
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University Federico II of Naples, 80131 Naples, Italy (L.B.)
| |
Collapse
|
3
|
Elziny S, Sran S, Yoon H, Corrigan RR, Page J, Ringland A, Lanier A, Lapidus S, Foreman J, Heinzen EL, Iffland P, Crino PB, Bedrosian TA. Loss of Slc35a2 alters development of the mouse cerebral cortex. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.29.569243. [PMID: 38077069 PMCID: PMC10705455 DOI: 10.1101/2023.11.29.569243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
Brain somatic variants in SLC35A2 are associated with clinically drug-resistant epilepsy and developmental brain malformations, including mild malformation of cortical development with oligodendroglial hyperplasia in epilepsy (MOGHE). SLC35A2 encodes a uridine diphosphate galactose translocator that is essential for protein glycosylation; however, the neurodevelopmental mechanisms by which SLC35A2 disruption leads to clinical and histopathological features remain unspecified. We hypothesized that focal knockout (KO) or knockdown (KD) of Slc35a2 in the developing mouse cortex would disrupt cerebral cortical development through altered neuronal migration and cause changes in network excitability. We used in utero electroporation (IUE) to introduce CRISPR/Cas9 and targeted guide RNAs or short-hairpin RNAs to achieve Slc35a2 KO or KD, respectively, during early corticogenesis. Following Slc35a2 KO or KD, we observed disrupted radial migration of transfected neurons evidenced by heterotopic cells located in lower cortical layers and in the sub-cortical white matter. Slc35a2 KO in neurons did not induce changes in oligodendrocyte number, suggesting that the oligodendroglial hyperplasia observed in MOGHE originates from distinct cell autonomous effects. Spontaneous seizures were not observed, but intracranial EEG recordings after focal KO showed a reduced seizure threshold following pentylenetetrazol injection. These results demonstrate that Slc35a2 KO or KD in vivo disrupts corticogenesis through altered neuronal migration.
Collapse
Affiliation(s)
- Soad Elziny
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Sahibjot Sran
- Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH, USA
| | - Hyojung Yoon
- Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH, USA
| | - Rachel R. Corrigan
- Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH, USA
| | - John Page
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Amanda Ringland
- Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH, USA
| | - Anna Lanier
- Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH, USA
| | - Sara Lapidus
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - James Foreman
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Erin L. Heinzen
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy and Department of Genetics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Philip Iffland
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Peter B. Crino
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Tracy A. Bedrosian
- Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH, USA
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
| |
Collapse
|
4
|
Elziny S, Crino PB, Winawer M. SLC35A2 somatic variants in drug resistant epilepsy: FCD and MOGHE. Neurobiol Dis 2023; 187:106299. [PMID: 37739137 PMCID: PMC10994450 DOI: 10.1016/j.nbd.2023.106299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 09/05/2023] [Accepted: 09/13/2023] [Indexed: 09/24/2023] Open
Abstract
De novo somatic (post-zygotic) gene mutations affecting neuroglial progenitor cell types in embryonic cerebral cortex are increasingly identified in patients with drug resistant epilepsy (DRE) associated with malformations of cortical development, in particular, focal cortical dysplasias (FCD). Somatic variants in at least 16 genes have been linked to FCD type II, all encoding components of the mechanistic target of rapamycin (mTOR) pathway. FCD type II is characterized histopathologically by cytomegalic dysmorphic neurons and balloon cells. In contrast, the molecular pathogenesis of FCD I subtypes is less well understood, and histological features are characterized by alterations in columnar or laminar organization without cytomegalic dysmorphic neurons or balloon cells. In 2018, we reported somatic mutations in Solute Carrier Family 35 member A2 (SLC35A2) linked to DRE underlying FCD type I and subsequently to a new histopathological phenotype: excess oligodendrocytes and heterotopic neurons in subcortical white matter known as MOGHE (mild malformation of cortical development with oligodendroglial hyperplasia). These discoveries opened the door to studies linking somatic mutations to FCD. In this review, we discuss the biology of SLC35A2 somatic mutations in epilepsy in FCD and MOGHE, and insights into SLC35A2 epilepsy pathogenesis, describing progress to date and critical areas for investigation.
Collapse
Affiliation(s)
- Soad Elziny
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Peter B Crino
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Melodie Winawer
- Department of Neurology, Columbia University, New York, NY, United States of America.
| |
Collapse
|
5
|
Huang Z, Yang H, Lao J, Deng W. Solute carrier family 35 member A2 (SLC35A2) is a prognostic biomarker and correlated with immune infiltration in stomach adenocarcinoma. PLoS One 2023; 18:e0287303. [PMID: 37467193 DOI: 10.1371/journal.pone.0287303] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 06/03/2023] [Indexed: 07/21/2023] Open
Abstract
BACKGROUND Solute carrier family 35 member A2 (SLC35A2) located on the X chromosome is considered involved in the UDP-galactose transport from cytosol to Golgi apparatus and endoplasmic reticulum. It has been reported that the SLC35A2 expression is associated with carcinogenesis in recent studies, however, its specific roles in cancer progression have not been exhaustively elucidated. Herein, a system analysis was conducted to evaluate the role of SLC35A2 in prognostic, and immunology in stomach adenocarcinoma (STAD). METHODS The TIMER, GEPIA, UALCAN, Kaplan-Meier Plotter were employed to explore the SLC35A2 expression pattern and prognostic value in STAD. Genomic alterations were searched through the MEXPRESS and cBioPortal platforms. The LinkedOmics, GEPIA and Metascape databases were employed to explore the biological processes. The TIMER and TISIDB websites were utilized to investigate the relationships between SLC35A2 expression and immune cell infiltration. The associations between SLC35A2 expression and tumor mutational burden (TMB), microsatellite instability (MSI) in pan-cancer were explored using the SangerBox database. RESULTS Compared to the normal gastric mucosa, SLC35A2 expression was significantly increased in STAD tissues, accompanied by the robust relationships with tumor grade, histological subtypes, TP53 mutation status, TMB and prognosis. SLC35A2 and its co-expression genes played the primarily roles in purine metabolism and purinosome, including the asparagine N-linked glycosylation, protein processing in endoplasmic reticulum, regulation of transcription involved in G1/S transition of mitotic cell cycle, with the potential to participate in the regulation of VEGFA-VEGFR2 signaling pathway. Concurrently, SLC35A2 expression was correlated with macrophages and CD4+T lymphocytes infiltration in STAD. CONCLUSIONS Our study has proposed that SLC35A2 correlated with immune cell infiltration could serve as a prognostic biomarker in STAD.
Collapse
Affiliation(s)
- Zigao Huang
- Department of Gastrointestinal Surgery, The First People's Hospital of Qinzhou, Qinzhou, Guangxi Zhuang Autonomous Region, China
| | - Hong Yang
- Department of Vascular Surgery, The First People's Hospital of Qinzhou, Qinzhou, Guangxi Zhuang Autonomous Region, China
| | - Jingmao Lao
- Department of Gastrointestinal Surgery, The First People's Hospital of Qinzhou, Qinzhou, Guangxi Zhuang Autonomous Region, China
| | - Wei Deng
- Department of Gastrointestinal Surgery, The First People's Hospital of Qinzhou, Qinzhou, Guangxi Zhuang Autonomous Region, China
| |
Collapse
|
6
|
Pradeep P, Kang H, Lee B. Glycosylation and behavioral symptoms in neurological disorders. Transl Psychiatry 2023; 13:154. [PMID: 37156804 PMCID: PMC10167254 DOI: 10.1038/s41398-023-02446-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 04/19/2023] [Accepted: 04/24/2023] [Indexed: 05/10/2023] Open
Abstract
Glycosylation, the addition of glycans or carbohydrates to proteins, lipids, or other glycans, is a complex post-translational modification that plays a crucial role in cellular function. It is estimated that at least half of all mammalian proteins undergo glycosylation, underscoring its importance in the functioning of cells. This is reflected in the fact that a significant portion of the human genome, around 2%, is devoted to encoding enzymes involved in glycosylation. Changes in glycosylation have been linked to various neurological disorders, including Alzheimer's disease, Parkinson's disease, autism spectrum disorder, and schizophrenia. Despite its widespread occurrence, the role of glycosylation in the central nervous system remains largely unknown, particularly with regard to its impact on behavioral abnormalities in brain diseases. This review focuses on examining the role of three types of glycosylation: N-glycosylation, O-glycosylation, and O-GlcNAcylation, in the manifestation of behavioral and neurological symptoms in neurodevelopmental, neurodegenerative, and neuropsychiatric disorders.
Collapse
Affiliation(s)
- Prajitha Pradeep
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, 34126, South Korea
- IBS School, University of Science and Technology (UST), Daejeon, 34113, South Korea
| | - Hyeyeon Kang
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, 34126, South Korea
- Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
| | - Boyoung Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, 34126, South Korea.
- IBS School, University of Science and Technology (UST), Daejeon, 34113, South Korea.
- Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea.
| |
Collapse
|
7
|
Kodríková R, Pakanová Z, Krchňák M, Šedivá M, Šesták S, Květoň F, Beke G, Šalingová A, Skalická K, Brennerová K, Jančová E, Baráth P, Mucha J, Nemčovič M. N-Glycoprofiling of SLC35A2-CDG: Patient with a Novel Hemizygous Variant. Biomedicines 2023; 11:biomedicines11020580. [PMID: 36831116 PMCID: PMC9952902 DOI: 10.3390/biomedicines11020580] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 02/01/2023] [Accepted: 02/14/2023] [Indexed: 02/18/2023] Open
Abstract
Congenital disorders of glycosylation (CDG) are a group of rare inherited metabolic disorders caused by a defect in the process of protein glycosylation. In this work, we present a comprehensive glycoprofile analysis of a male patient with a novel missense variant in the SLC35A2 gene, coding a galactose transporter that translocates UDP-galactose from the cytosol to the lumen of the endoplasmic reticulum and Golgi apparatus. Isoelectric focusing of serum transferrin, which resulted in a CDG type II pattern, was followed by structural analysis of transferrin and serum N-glycans, as well as the analysis of apolipoprotein CIII O-glycans by mass spectrometry. An abnormal serum N-glycoprofile with significantly increased levels of agalactosylated (Hex3HexNAc4-5 and Hex3HexNAc5Fuc1) and monogalactosylated (Hex4HexNAc4 ± NeuAc1) N-glycans was observed. Additionally, whole exome sequencing and Sanger sequencing revealed de novo hemizygous c.461T > C (p.Leu154Pro) mutation in the SLC35A2 gene. Based on the combination of biochemical, analytical, and genomic approaches, the set of distinctive N-glycan biomarkers was characterized. Potentially, the set of identified aberrant N-glycans can be specific for other variants causing SLC35A2-CDG and can distinguish this disorder from the other CDGs or other defects in the galactose metabolism.
Collapse
Affiliation(s)
- Rebeka Kodríková
- Institute of Chemistry, Centre of Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia
| | - Zuzana Pakanová
- Institute of Chemistry, Centre of Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia
- Correspondence:
| | - Maroš Krchňák
- Institute of Chemistry, Centre of Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia
| | - Mária Šedivá
- Institute of Chemistry, Centre of Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia
| | - Sergej Šesták
- Institute of Chemistry, Centre of Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia
| | - Filip Květoň
- Institute of Chemistry, Centre of Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia
| | - Gábor Beke
- Institute of Chemistry, Centre of Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia
- Department of Genomics and Biotechnology, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia
| | - Anna Šalingová
- National Institute of Children’s Diseases, Center for Inherited Metabolic Disorders, Limbová 1, 833 40 Bratislava, Slovakia
| | - Katarína Skalická
- Laboratory of Clinical and Molecular Genetics, National Institute of Children’s Diseases, Limbová 1, 833 40 Bratislava, Slovakia
| | - Katarína Brennerová
- Department of Paediatrics, Faculty of Medicine of Comenius University and National Institute for Children’s Diseases, Limbová 1, 833 40 Bratislava, Slovakia
| | - Emília Jančová
- Department of Paediatrics, Faculty of Medicine of Comenius University and National Institute for Children’s Diseases, Limbová 1, 833 40 Bratislava, Slovakia
| | - Peter Baráth
- Institute of Chemistry, Centre of Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia
| | - Ján Mucha
- Institute of Chemistry, Centre of Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia
| | - Marek Nemčovič
- Institute of Chemistry, Centre of Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava, Slovakia
| |
Collapse
|
8
|
Barba C, Blumcke I, Winawer MR, Hartlieb T, Kang HC, Grisotto L, Chipaux M, Bien CG, Heřmanovská B, Porter BE, Lidov HGW, Cetica V, Woermann FG, Lopez-Rivera JA, Canoll PD, Mader I, D'Incerti L, Baldassari S, Yang E, Gaballa A, Vogel H, Straka B, Macconi L, Polster T, Grant GA, Krsková L, Shin HJ, Ko A, Crino PB, Krsek P, Lee JH, Lal D, Baulac S, Poduri A, Guerrini R. Clinical Features, Neuropathology, and Surgical Outcome in Patients With Refractory Epilepsy and Brain Somatic Variants in the SLC35A2 Gene. Neurology 2023; 100:e528-e542. [PMID: 36307217 PMCID: PMC9931085 DOI: 10.1212/wnl.0000000000201471] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 09/09/2022] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND AND OBJECTIVES The SLC35A2 gene, located at chromosome Xp11.23, encodes for a uridine diphosphate-galactose transporter. We describe clinical, genetic, neuroimaging, EEG, and histopathologic findings and assess possible predictors of postoperative seizure and cognitive outcome in 47 patients with refractory epilepsy and brain somatic SLC35A2 gene variants. METHODS This is a retrospective multicenter study where we performed a descriptive analysis and classical hypothesis testing. We included the variables of interest significantly associated with the outcomes in the generalized linear models. RESULTS Two main phenotypes were associated with brain somatic SLC35A2 variants: (1) early epileptic encephalopathy (EE, 39 patients) with epileptic spasms as the predominant seizure type and moderate to severe intellectual disability and (2) drug-resistant focal epilepsy (DR-FE, 8 patients) associated with normal/borderline cognitive function and specific neuropsychological deficits. Brain MRI was abnormal in all patients with EE and in 50% of those with DR-FE. Histopathology review identified mild malformation of cortical development with oligodendroglial hyperplasia in epilepsy in 44/47 patients and was inconclusive in 3. The 47 patients harbored 42 distinct mosaic SLC35A2 variants, including 14 (33.3%) missense, 13 (30.9%) frameshift, 10 (23.8%) nonsense, 4 (9.5%) in-frame deletions/duplications, and 1 (2.4%) splicing variant. Variant allele frequencies (VAFs) ranged from 1.4% to 52.6% (mean VAF: 17.3 ± 13.5). At last follow-up (35.5 ± 21.5 months), 30 patients (63.8%) were in Engel Class I, of which 26 (55.3%) were in Class IA. Cognitive performances remained unchanged in most patients after surgery. Regression analyses showed that the probability of achieving both Engel Class IA and Class I outcomes, adjusted by age at seizure onset, was lower when the duration of epilepsy increased and higher when postoperative EEG was normal or improved. Lower brain VAF was associated with improved postoperative cognitive outcome in the analysis of associations, but this finding was not confirmed in regression analyses. DISCUSSION Brain somatic SLC35A2 gene variants are associated with 2 main clinical phenotypes, EE and DR-FE, and a histopathologic diagnosis of MOGHE. Additional studies will be needed to delineate any possible correlation between specific genetic variants, mutational load in the epileptogenic tissue, and surgical outcomes.
Collapse
Affiliation(s)
- Carmen Barba
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Ingmar Blumcke
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Melodie R Winawer
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Till Hartlieb
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Hoon-Chul Kang
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Laura Grisotto
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Mathilde Chipaux
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Christian G Bien
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Barbora Heřmanovská
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Brenda E Porter
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Hart G W Lidov
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Valentina Cetica
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Friedrich G Woermann
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Javier A Lopez-Rivera
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Peter D Canoll
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Irina Mader
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Ludovico D'Incerti
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Sara Baldassari
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Edward Yang
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Ahmed Gaballa
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Hannes Vogel
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Barbora Straka
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Letizia Macconi
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Tilman Polster
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Gerald A Grant
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Lenka Krsková
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Hui Jin Shin
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Ara Ko
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Peter B Crino
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Pavel Krsek
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Jeong Ho Lee
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Dennis Lal
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Stéphanie Baulac
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Annapurna Poduri
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| | - Renzo Guerrini
- From the IRCCS Meyer Children's Hospital (C.B., V.C., L.D.I., L.M., R.G.), Florence, Italy; University of Florence (C.B., L.G., R.G.), Florence, Italy; University Hospital Erlangen (I.B.), Germany; Columbia University (M.R.W., P.D.C.), New York, NY; Neurorehabilitation and Epileptology (T.H., I.M.), Vogtareuth, Germany; PMU Salzburg (T.H.), Austria; Yonsei University College of Medicine (H.-C.K., H.J.S.), Seoul, Republic of Korea; Rothschild Foundation Hospital (M.C.), Paris, France; Krankenhaus Mara (C.G.B., F.G.W., A.G., T.P.), Bielefeld University, Medical School, Germany; Charles University (B.H., B.S., L.K., P.K.), 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; Stanford University (B.E.P., H.V.), School of Medicine Stanford, CA; Boston Children's Hospital and Harvard Medical School (H.G.W.L., E.Y., A.P.), MA; Society of Epilepsy Research (F.G.W.), Bielefeld, Germany; Case Western Reserve University (J.A.L.-R.), OH; Cleveland Clinic (J.A.L.-R., D.L.), Cleveland, OH; Sorbonne University (Sara Baldassari, Stéphanie Baulac), Paris Brain Institute (ICM), INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, France; Lucile Packard Children's Hospital at Stanford University (G.A.G.), School of Medicine Stanford, CA; Korea Advanced Institute of Science and Technology (A.K., J.H.L.), Daejeon, South Korea; University of Maryland School of Medicine (P.B.C.), Baltimore, MD; and Broad Institute of Harvard and M.I.T (D.L.), Cambridge, MA
| |
Collapse
|
9
|
Paprocka J. Neurological Consequences of Congenital Disorders of Glycosylation. ADVANCES IN NEUROBIOLOGY 2023; 29:219-253. [PMID: 36255677 DOI: 10.1007/978-3-031-12390-0_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The chapter is devoted to neurological aspects of congenital disorders of glycosylation (CDG). At the beginning, the various types of CDG with neurological presentation of symptoms are summarized. Then, the occurrence of various neurological constellation of abnormalities (for example: epilepsy, brain anomalies on neuroimaging, ataxia, stroke-like episodes, autistic features) in different CDG types are discussed followed by data on possible biomarkers and limited treatment options.
Collapse
Affiliation(s)
- Justyna Paprocka
- Department of Pediatric Neurology, Faculty of Medical Sciences, Medical University of Silesia, Katowice, Poland.
| |
Collapse
|
10
|
Schwartz CE, Louie RJ, Toutain A, Skinner C, Friez MJ, Stevenson RE. X-Linked intellectual disability update 2022. Am J Med Genet A 2023; 191:144-159. [PMID: 36300573 DOI: 10.1002/ajmg.a.63008] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 07/28/2022] [Accepted: 09/29/2022] [Indexed: 12/14/2022]
Abstract
Genes that are involved in the transcription process, mitochondrial function, glycoprotein metabolism, and ubiquitination dominate the list of 21 new genes associated with X-linked intellectual disability since the last update in 2017. The new genes were identified by sequencing of candidate genes (2), the entire X-chromosome (2), the whole exome (15), or the whole genome (2). With these additions, 42 (21%) of the 199 named XLID syndromes and 27 (25%) of the 108 numbered nonsyndromic XLID families remain to be resolved at the molecular level. Although the pace of discovery of new XLID genes has slowed during the past 5 years, the density of genes on the X chromosome that cause intellectual disability still appears to be twice the density of intellectual disability genes on the autosomes.
Collapse
Affiliation(s)
| | | | - Annick Toutain
- Department of Medical Genetics, Centre Hospitalier Universitaire, Tours, France
| | - Cindy Skinner
- Greenwood Genetic Center, Greenwood, South Carolina, USA
| | | | | |
Collapse
|
11
|
Gan Y, Wei Z, Liu C, Li G, Feng Y, Deng Y. Solute carrier transporter disease and developmental and epileptic encephalopathy. Front Neurol 2022; 13:1013903. [PMID: 36419532 PMCID: PMC9676364 DOI: 10.3389/fneur.2022.1013903] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 09/07/2022] [Indexed: 09/14/2023] Open
Abstract
The International League Against Epilepsy officially revised its classification in 2017, which amended "epileptic encephalopathy" to "developmental and epileptic encephalopathy". With the development of genetic testing technology, an increasing number of genes that cause developmental and epileptic encephalopathies are being identified. Among these, solute transporter dysfunction is part of the etiology of developmental and epileptic encephalopathies. Solute carrier transporters play an essential physiological function in the human body, and their dysfunction is associated with various human diseases. Therefore, in-depth studies of developmental and epileptic encephalopathies caused by solute carrier transporter dysfunction can help develop new therapeutic modalities to facilitate the treatment of refractory epilepsy and improve patient prognosis. In this article, the concept of transporter protein disorders is first proposed, and nine developmental and epileptic encephalopathies caused by solute carrier transporter dysfunction are described in detail in terms of pathogenesis, clinical manifestations, ancillary tests, and precise treatment to provide ideas for the precise treatment of epilepsy.
Collapse
Affiliation(s)
- Yajing Gan
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Zihan Wei
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Chao Liu
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Guoyan Li
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Yan Feng
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Yanchun Deng
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
- Xijing Institute of Epilepsy and Encephalopathy, Xi'an, China
| |
Collapse
|
12
|
Lai D, Gade M, Yang E, Koh HY, Lu J, Walley NM, Buckley AF, Sands TT, Akman CI, Mikati MA, McKhann GM, Goldman JE, Canoll P, Alexander AL, Park KL, Von Allmen GK, Rodziyevska O, Bhattacharjee MB, Lidov HGW, Vogel H, Grant GA, Porter BE, Poduri AH, Crino PB, Heinzen EL. Somatic variants in diverse genes leads to a spectrum of focal cortical malformations. Brain 2022; 145:2704-2720. [PMID: 35441233 PMCID: PMC9612793 DOI: 10.1093/brain/awac117] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 02/19/2022] [Accepted: 03/13/2022] [Indexed: 11/14/2022] Open
Abstract
Post-zygotically acquired genetic variants, or somatic variants, that arise during cortical development have emerged as important causes of focal epilepsies, particularly those due to malformations of cortical development. Pathogenic somatic variants have been identified in many genes within the PI3K-AKT-mTOR-signalling pathway in individuals with hemimegalencephaly and focal cortical dysplasia (type II), and more recently in SLC35A2 in individuals with focal cortical dysplasia (type I) or non-dysplastic epileptic cortex. Given the expanding role of somatic variants across different brain malformations, we sought to delineate the landscape of somatic variants in a large cohort of patients who underwent epilepsy surgery with hemimegalencephaly or focal cortical dysplasia. We evaluated samples from 123 children with hemimegalencephaly (n = 16), focal cortical dysplasia type I and related phenotypes (n = 48), focal cortical dysplasia type II (n = 44), or focal cortical dysplasia type III (n = 15). We performed high-depth exome sequencing in brain tissue-derived DNA from each case and identified somatic single nucleotide, indel and large copy number variants. In 75% of individuals with hemimegalencephaly and 29% with focal cortical dysplasia type II, we identified pathogenic variants in PI3K-AKT-mTOR pathway genes. Four of 48 cases with focal cortical dysplasia type I (8%) had a likely pathogenic variant in SLC35A2. While no other gene had multiple disease-causing somatic variants across the focal cortical dysplasia type I cohort, four individuals in this group had a single pathogenic or likely pathogenic somatic variant in CASK, KRAS, NF1 and NIPBL, genes previously associated with neurodevelopmental disorders. No rare pathogenic or likely pathogenic somatic variants in any neurological disease genes like those identified in the focal cortical dysplasia type I cohort were found in 63 neurologically normal controls (P = 0.017), suggesting a role for these novel variants. We also identified a somatic loss-of-function variant in the known epilepsy gene, PCDH19, present in a small number of alleles in the dysplastic tissue from a female patient with focal cortical dysplasia IIIa with hippocampal sclerosis. In contrast to focal cortical dysplasia type II, neither focal cortical dysplasia type I nor III had somatic variants in genes that converge on a unifying biological pathway, suggesting greater genetic heterogeneity compared to type II. Importantly, we demonstrate that focal cortical dysplasia types I, II and III are associated with somatic gene variants across a broad range of genes, many associated with epilepsy in clinical syndromes caused by germline variants, as well as including some not previously associated with radiographically evident cortical brain malformations.
Collapse
Affiliation(s)
- Dulcie Lai
- Division of Pharmacology and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Meethila Gade
- Division of Pharmacology and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Edward Yang
- Department of Radiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Hyun Yong Koh
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA.,Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Jinfeng Lu
- Division of Pharmacology and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Nicole M Walley
- Division of Medical Genetics, Department of Pediatrics, Duke University School of Medicine, Durham, NC 27710, USA
| | - Anne F Buckley
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA
| | - Tristan T Sands
- Institute for Genomic Medicine, Columbia University Medical Center, New York, NY 10032, USA.,Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA
| | - Cigdem I Akman
- Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA
| | - Mohamad A Mikati
- Department of Neurobiology, Duke University, Durham, NC 27708, USA.,Division of Pediatric Neurology, Duke University Medical Center, Durham, NC 27710, USA
| | - Guy M McKhann
- Department of Neurosurgery, Columbia University, New York Presbyterian Hospital, New York, NY 10032, USA
| | - James E Goldman
- Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA
| | - Peter Canoll
- Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA
| | - Allyson L Alexander
- Department of Neurosurgery, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Kristen L Park
- Department of Pediatrics and Neurology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Gretchen K Von Allmen
- Department of Neurology, McGovern Medical School, Houston, TX 77030, USA.,Division of Child Neurology, Department of Pediatrics, McGovern Medical School, Houston, TX 77030, USA
| | - Olga Rodziyevska
- Division of Child Neurology, Department of Pediatrics, McGovern Medical School, Houston, TX 77030, USA
| | | | - Hart G W Lidov
- Department of Pathology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Hannes Vogel
- Department of Pathology, Stanford University, School of Medicine, Stanford, CA 94305, USA
| | - Gerald A Grant
- Department of Neurosurgery, Lucile Packard Children's Hospital at Stanford, School of Medicine, Stanford, CA 94305, USA
| | - Brenda E Porter
- Department of Neurology and Neurological Sciences, Stanford University, School of Medicine, Stanford, CA 94305, USA
| | - Annapurna H Poduri
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA.,Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Peter B Crino
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Erin L Heinzen
- Division of Pharmacology and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Department of Genetics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| |
Collapse
|
13
|
Delivery of Nucleotide Sugars to the Mammalian Golgi: A Very Well (un)Explained Story. Int J Mol Sci 2022; 23:ijms23158648. [PMID: 35955785 PMCID: PMC9368800 DOI: 10.3390/ijms23158648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/31/2022] [Accepted: 08/02/2022] [Indexed: 11/25/2022] Open
Abstract
Nucleotide sugars (NSs) serve as substrates for glycosylation reactions. The majority of these compounds are synthesized in the cytoplasm, whereas glycosylation occurs in the endoplasmic reticulum (ER) and Golgi lumens, where catalytic domains of glycosyltransferases (GTs) are located. Therefore, translocation of NS across the organelle membranes is a prerequisite. This process is thought to be mediated by a group of multi-transmembrane proteins from the SLC35 family, i.e., nucleotide sugar transporters (NSTs). Despite many years of research, some uncertainties/inconsistencies related with the mechanisms of NS transport and the substrate specificities of NSTs remain. Here we present a comprehensive review of the NS import into the mammalian Golgi, which consists of three major parts. In the first part, we provide a historical view of the experimental approaches used to study NS transport and evaluate the most important achievements. The second part summarizes various aspects of knowledge concerning NSTs, ranging from subcellular localization up to the pathologies related with their defective function. In the third part, we present the outcomes of our research performed using mammalian cell-based models and discuss its relevance in relation to the general context.
Collapse
|
14
|
Kot M, Mazurkiewicz E, Wiktor M, Wiertelak W, Mazur AJ, Rahalevich A, Olczak M, Maszczak-Seneczko D. SLC35A2 Deficiency Promotes an Epithelial-to-Mesenchymal Transition-like Phenotype in Madin–Darby Canine Kidney Cells. Cells 2022; 11:cells11152273. [PMID: 35892570 PMCID: PMC9331475 DOI: 10.3390/cells11152273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 07/15/2022] [Accepted: 07/20/2022] [Indexed: 11/16/2022] Open
Abstract
In mammalian cells, SLC35A2 delivers UDP–galactose for galactosylation reactions that take place predominantly in the Golgi lumen. Mutations in the corresponding gene cause a subtype of a congenital disorder of glycosylation (SLC35A2-CDG). Although more and more patients are diagnosed with SLC35A2-CDG, the link between defective galactosylation and disease symptoms is not fully understood. According to a number of reports, impaired glycosylation may trigger the process of epithelial-to-mesenchymal transition (EMT). We therefore examined whether the loss of SLC35A2 activity would promote EMT in a non-malignant epithelial cell line. For this purpose, we knocked out the SLC35A2 gene in Madin–Darby canine kidney (MDCK) cells. The resulting clones adopted an elongated, spindle-shaped morphology and showed impaired cell–cell adhesion. Using qPCR and western blotting, we revealed down-regulation of E-cadherin in the knockouts, while the fibronectin and vimentin levels were elevated. Moreover, the knockout cells displayed reorganization of vimentin intermediate filaments and altered subcellular distribution of a vimentin-binding protein, formiminotransferase cyclodeaminase (FTCD). Furthermore, depletion of SLC35A2 triggered Golgi compaction. Finally, the SLC35A2 knockouts displayed increased motility and invasiveness. In conclusion, SLC35A2-deficient MDCK cells showed several hallmarks of EMT. Our findings point to a novel role for SLC35A2 as a gatekeeper of the epithelial phenotype.
Collapse
Affiliation(s)
- Magdalena Kot
- Department of Cell Pathology, Faculty of Biotechnology, University of Wroclaw, 14A F. Joliot-Curie St., 50-383 Wroclaw, Poland; (M.K.); (E.M.); (A.J.M.)
| | - Ewa Mazurkiewicz
- Department of Cell Pathology, Faculty of Biotechnology, University of Wroclaw, 14A F. Joliot-Curie St., 50-383 Wroclaw, Poland; (M.K.); (E.M.); (A.J.M.)
| | - Maciej Wiktor
- Department of Biochemistry, Faculty of Biotechnology, University of Wroclaw, 14A F. Joliot-Curie St., 50-383 Wroclaw, Poland; (M.W.); (W.W.); (A.R.); (M.O.)
| | - Wojciech Wiertelak
- Department of Biochemistry, Faculty of Biotechnology, University of Wroclaw, 14A F. Joliot-Curie St., 50-383 Wroclaw, Poland; (M.W.); (W.W.); (A.R.); (M.O.)
| | - Antonina Joanna Mazur
- Department of Cell Pathology, Faculty of Biotechnology, University of Wroclaw, 14A F. Joliot-Curie St., 50-383 Wroclaw, Poland; (M.K.); (E.M.); (A.J.M.)
| | - Andrei Rahalevich
- Department of Biochemistry, Faculty of Biotechnology, University of Wroclaw, 14A F. Joliot-Curie St., 50-383 Wroclaw, Poland; (M.W.); (W.W.); (A.R.); (M.O.)
| | - Mariusz Olczak
- Department of Biochemistry, Faculty of Biotechnology, University of Wroclaw, 14A F. Joliot-Curie St., 50-383 Wroclaw, Poland; (M.W.); (W.W.); (A.R.); (M.O.)
| | - Dorota Maszczak-Seneczko
- Department of Biochemistry, Faculty of Biotechnology, University of Wroclaw, 14A F. Joliot-Curie St., 50-383 Wroclaw, Poland; (M.W.); (W.W.); (A.R.); (M.O.)
- Correspondence:
| |
Collapse
|
15
|
McGinn RJ, Von Stein EL, Summers Stromberg JE, Li Y. Precision medicine in epilepsy. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2022; 190:147-188. [DOI: 10.1016/bs.pmbts.2022.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
16
|
Liver Involvement in Congenital Disorders of Glycosylation: A Systematic Review. J Pediatr Gastroenterol Nutr 2021; 73:444-454. [PMID: 34173795 PMCID: PMC9255677 DOI: 10.1097/mpg.0000000000003209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
An ever-increasing number of disturbances in glycosylation have been described to underlie certain unexplained liver diseases presenting either almost isolated or in a multi-organ context. We aimed to update previous literature screenings which had identified up to 23 forms of congenital disorders of glycosylation (CDG) with associated liver disease. We conducted a comprehensive literature search of three scientific electronic databases looking at articles published during the last 20 years (January 2000-October 2020). Eligible studies were case reports/series reporting liver involvement in CDG patients. Our systematic review led us to point out 41 forms of CDG where the liver is primarily affected (n = 7) or variably involved in a multisystem disease with mandatory neurological abnormalities (n = 34). Herein we summarize individual clinical and laboratory presentation characteristics of these 41 CDG and outline their main presentation and diagnostic cornerstones with the aid of two synoptic tables. Dietary supplementation strategies have hitherto been investigated only in seven of these CDG types with liver disease, with a wide range of results. In conclusion, the systematic review recognized a liver involvement in a somewhat larger number of CDG variants corresponding to about 30% of the total of CDG so far reported, and it is likely that the number may increase further. This information could assist in an earlier correct diagnosis and a possibly proper management of these disorders.
Collapse
|
17
|
Park JH, Marquardt T. Treatment Options in Congenital Disorders of Glycosylation. Front Genet 2021; 12:735348. [PMID: 34567084 PMCID: PMC8461064 DOI: 10.3389/fgene.2021.735348] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 08/23/2021] [Indexed: 12/15/2022] Open
Abstract
Despite advances in the identification and diagnosis of congenital disorders of glycosylation (CDG), treatment options remain limited and are often constrained to symptomatic management of disease manifestations. However, recent years have seen significant advances in treatment and novel therapies aimed both at the causative defect and secondary disease manifestations have been transferred from bench to bedside. In this review, we aim to give a detailed overview of the available therapies and rising concepts to treat these ultra-rare diseases.
Collapse
Affiliation(s)
- Julien H Park
- Department of General Pediatrics, Metabolic Diseases, University Children's Hospital Münster, Münster, Germany
| | - Thorsten Marquardt
- Department of General Pediatrics, Metabolic Diseases, University Children's Hospital Münster, Münster, Germany
| |
Collapse
|
18
|
Brand BA, Blesson AE, Smith-Hicks CL. The Impact of X-Chromosome Inactivation on Phenotypic Expression of X-Linked Neurodevelopmental Disorders. Brain Sci 2021; 11:brainsci11070904. [PMID: 34356138 PMCID: PMC8305405 DOI: 10.3390/brainsci11070904] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 06/16/2021] [Accepted: 06/20/2021] [Indexed: 12/20/2022] Open
Abstract
Nearly 20% of genes located on the X chromosome are associated with neurodevelopmental disorders (NDD) due to their expression and role in brain functioning. Given their location, several of these genes are either subject to or can escape X-chromosome inactivation (XCI). The degree to which genes are subject to XCI can influence the NDD phenotype between males and females. We provide a general review of X-linked NDD genes in the context of XCI and detailed discussion of the sex-based differences related to MECP2 and FMR1, two common X-linked causes of NDD that are subject to XCI. Understanding the effects of XCI on phenotypic expression of NDD genes may guide the development of stratification biomarkers in X-linked disorders.
Collapse
Affiliation(s)
- Boudewien A Brand
- Center for Autism and Related Disorders, Kennedy Krieger Institute, Baltimore, MD 21205, USA; (B.A.B.); (A.E.B.)
| | - Alyssa E Blesson
- Center for Autism and Related Disorders, Kennedy Krieger Institute, Baltimore, MD 21205, USA; (B.A.B.); (A.E.B.)
| | - Constance L. Smith-Hicks
- Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
- Correspondence:
| |
Collapse
|
19
|
Abuduxikuer K, Wang JS. Four New Cases of SLC35A2-CDG With Novel Mutations and Clinical Features. Front Genet 2021; 12:658786. [PMID: 34122512 PMCID: PMC8191577 DOI: 10.3389/fgene.2021.658786] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 04/27/2021] [Indexed: 11/13/2022] Open
Abstract
SLC35A2-CDG is a rare type of X-linked CDG with more than 60 reported cases. We retrospectively analyzed clinical phenotypes and SLC35A2 genotypes of four cases of SLC35A2-CDG from four unrelated families of Han ethnicity in China. All patients had infantile onset epilepsies that were completely or partly resistant to multiple anti-epileptic medications or ketogenic diet. Three patients had severe developmental delay. All patients were female patients carrying de novo deleterious mutations in SLC35A2 (NM_001042498.2) gene, including one canonical splice-site mutation (c.426+1G > A), one large deletion (c.-322_c.274+1del), and two frameshift mutations leading to premature stop codon (c.781delC/p.Arg289ValfsTer88 and c.601delG/p.Ala201GlnfsTer148). Novel clinical features in some of our patients include anemia, hypertriglyceridemia, hypertonia, small ears, extra folds on earlobes, and maternal oligohydramnios or hypothyroidism during pregnancy. In one patient, concomitant Marfan syndrome was confirmed for having positive family history, carrying a heterozygous known disease-causing mutation in FBN1 gene (c.7240C > T/p.Arg2414Ter), and presence of typical features (rachnodactyly, ventrical septal defect, and mitral valve regurgitation). In conclusion, we expanded clinical phenotype and genetic mutation spectrum of SLC35A2-CDG by reporting four new cases with novel pathogenic variants and novel clinical features.
Collapse
Affiliation(s)
| | - Jian-She Wang
- Department of Hepatology, Children's Hospital of Fudan University, Shanghai, China
| |
Collapse
|
20
|
Conte F, van Buuringen N, Voermans NC, Lefeber DJ. Galactose in human metabolism, glycosylation and congenital metabolic diseases: Time for a closer look. Biochim Biophys Acta Gen Subj 2021; 1865:129898. [PMID: 33878388 DOI: 10.1016/j.bbagen.2021.129898] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/30/2021] [Accepted: 04/06/2021] [Indexed: 12/12/2022]
Abstract
Galactose is an essential carbohydrate for cellular metabolism, as it contributes to energy production and storage in several human tissues while also being a precursor for glycosylation. Galactosylated glycoconjugates, such as glycoproteins, keratan sulfate-containing proteoglycans and glycolipids, exert a plethora of biological functions, including structural support, cellular adhesion, intracellular signaling and many more. The biological relevance of galactose is further entailed by the number of pathogenic conditions consequent to defects in galactosylation and galactose homeostasis. The growing number of rare congenital disorders involving galactose along with its recent therapeutical applications are drawing increasing attention to galactose metabolism. In this review, we aim to draw a comprehensive overview of the biological functions of galactose in human cells, including its metabolism and its role in glycosylation, and to provide a systematic description of all known congenital metabolic disorders resulting from alterations of its homeostasis.
Collapse
Affiliation(s)
- Federica Conte
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands.
| | - Nicole van Buuringen
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Nicol C Voermans
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands.
| | - Dirk J Lefeber
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands; Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands.
| |
Collapse
|
21
|
Wada Y, Okamoto N. Apolipoprotein C-III O-glycoform profiling of 500 serum samples by matrix-assisted laser desorption/ionization mass spectrometry for diagnosis of congenital disorders of glycosylation. JOURNAL OF MASS SPECTROMETRY : JMS 2021; 56:e4597. [PMID: 32677746 DOI: 10.1002/jms.4597] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 06/06/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
Congenital disorders of glycosylation (CDG) are caused by defects in various genes governing glycoconjugate biosynthesis. Several responsible genes have been identified in the protein N-glycosylation process. Analyses of mucin-type core-1 O-glycoform of apolipoprotein C-III (apoCIII) have recently revealed combined N- and O-glycosylation defects. We applied matrix-assisted laser desorption/ionization mass spectrometry profiling of apoCIII glycoforms to 500 serum samples for CDG screening, and reference values were determined. The content of unglycosylated apoCIII was low in early infancy, indicating that the O-glycan occupancy should be assessed based on age-matched reference values. The samples from patients with mutations in the ALG1, ATP6V0A2, B4GALT1, COG2, GCS1, PGM1, SLC35A2, and TRAPPC11 genes were analyzed. B4GALT1- and TRAPPC11-CDG were accompanied by under-sialylation of O-glycans and are now recognized as combined N- and O-glycosylation disorders.
Collapse
Affiliation(s)
- Yoshinao Wada
- Department of Molecular Medicine, Osaka Women's and Children's Hospital (OWCH), Osaka, Japan
| | - Nobuhiko Okamoto
- Department of Molecular Medicine, Osaka Women's and Children's Hospital (OWCH), Osaka, Japan
| |
Collapse
|
22
|
Specchio N, Pepi C, De Palma L, Trivisano M, Vigevano F, Curatolo P. Neuroimaging and genetic characteristics of malformation of cortical development due to mTOR pathway dysregulation: clues for the epileptogenic lesions and indications for epilepsy surgery. Expert Rev Neurother 2021; 21:1333-1345. [PMID: 33754929 DOI: 10.1080/14737175.2021.1906651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Introduction: Malformation of cortical development (MCD) is strongly associated with drug-resistant epilepsies for which surgery to remove epileptogenic lesions is common. Two notable technological advances in this field are identification of the underlying genetic cause and techniques in neuroimaging. These now question how presurgical evaluation ought to be approached for 'mTORpathies.'Area covered: From review of published primary and secondary articles, the authors summarize evidence to consider focal cortical dysplasia (FCD), tuber sclerosis complex (TSC), and hemimegalencephaly (HME) collectively as MCD mTORpathies. The authors also consider the unique features of these related conditions with particular focus on the practicalities of using neuroimaging techniques currently available to define surgical targets and predict post-surgical outcome. Ultimately, the authors consider the surgical dilemmas faced for each condition.Expert opinion: Considering FCD, TSC, and HME collectively as mTORpathies has some merit; however, a unified approach to presurgical evaluation would seem unachievable. Nevertheless, the authors believe combining genetic-centered classification and morphologic findings using advanced imaging techniques will eventually form the basis of a paradigm when considering candidacy for early surgery.
Collapse
Affiliation(s)
- Nicola Specchio
- Rare and Complex Epilepsy Unit, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Member of European Reference Network EpiCARE, Rome, Italy
| | - Chiara Pepi
- Rare and Complex Epilepsy Unit, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Member of European Reference Network EpiCARE, Rome, Italy
| | - Luca De Palma
- Rare and Complex Epilepsy Unit, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Member of European Reference Network EpiCARE, Rome, Italy
| | - Marina Trivisano
- Rare and Complex Epilepsy Unit, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Member of European Reference Network EpiCARE, Rome, Italy
| | - Federico Vigevano
- Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS, Member of European Reference Network EpiCARE, Rome, Italy
| | - Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University, Rome, Italy
| |
Collapse
|
23
|
SLC35A2-CDG: Novel variant and review. Mol Genet Metab Rep 2021; 26:100717. [PMID: 33552911 PMCID: PMC7851840 DOI: 10.1016/j.ymgmr.2021.100717] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/17/2021] [Accepted: 01/18/2021] [Indexed: 12/11/2022] Open
Abstract
SLC35A2 encodes the X-linked transporter that carries uridine diphosphate (UDP)-galactose from the cytosol to the lumen of the Golgi apparatus and the endoplasmic reticulum. Pathogenic variants have been associated to a congenital disorder of glycosylation (CDG) with epileptic encephalopathy as a predominant feature. Among the sixty five patients described so far, a strong gender bias is observed as only seven patients are males. This work is a review and reports a SLC35A2-CDG in a male without epilepsy and with growth deficiency associated with decreased serum IGF1, minor neurological involvement, minor facial dysmorphism, and camptodactyly of fingers and toes. Sequence analysis revealed a hemizygosity for a novel de novo variant: c.233A > G (p.Lys78Arg) in SLC35A2. Further analysis of SLC35A2 sequence by comparing both orthologous and paralogous positions, revealed that not only the variant found in this study, but also most of the reported mutated positions are conserved in SLC35A2 orthologous, and many even in the paralogous SLC35A1 and SLC35A3. This is strong evidence that replacements at these positions will have a critical pathological effect and may also explain the gender bias observed among SLC35A2-CDG patients.
Collapse
|
24
|
Paprocka J, Jezela-Stanek A, Tylki-Szymańska A, Grunewald S. Congenital Disorders of Glycosylation from a Neurological Perspective. Brain Sci 2021; 11:brainsci11010088. [PMID: 33440761 PMCID: PMC7827962 DOI: 10.3390/brainsci11010088] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 01/01/2021] [Accepted: 01/04/2021] [Indexed: 12/11/2022] Open
Abstract
Most plasma proteins, cell membrane proteins and other proteins are glycoproteins with sugar chains attached to the polypeptide-glycans. Glycosylation is the main element of the post-translational transformation of most human proteins. Since glycosylation processes are necessary for many different biological processes, patients present a diverse spectrum of phenotypes and severity of symptoms. The most frequently observed neurological symptoms in congenital disorders of glycosylation (CDG) are: epilepsy, intellectual disability, myopathies, neuropathies and stroke-like episodes. Epilepsy is seen in many CDG subtypes and particularly present in the case of mutations in the following genes: ALG13, DOLK, DPAGT1, SLC35A2, ST3GAL3, PIGA, PIGW, ST3GAL5. On brain neuroimaging, atrophic changes of the cerebellum and cerebrum are frequently seen. Brain malformations particularly in the group of dystroglycanopathies are reported. Despite the growing number of CDG patients in the world and often neurological symptoms dominating in the clinical picture, the number of performed screening tests eg transferrin isoforms is systematically decreasing as broadened genetic testing is recently more favored. The aim of the review is the summary of selected neurological symptoms in CDG described in the literature in one paper. It is especially important for pediatric neurologists not experienced in the field of metabolic medicine. It may help to facilitate the diagnosis of this expanding group of disorders. Biochemically, this paper focuses on protein glycosylation abnormalities.
Collapse
Affiliation(s)
- Justyna Paprocka
- Department of Pediatric Neurology, Faculty of Medical Science in Katowice, Medical University of Silesia, 40-752 Katowice, Poland
- Correspondence: ; Tel.: +48-606-415-888
| | - Aleksandra Jezela-Stanek
- Department of Genetics and Clinical Immunology, National Institute of Tuberculosis and Lung Diseases, 01-138 Warsaw, Poland;
| | - Anna Tylki-Szymańska
- Department of Pediatrics, Nutrition and Metabolic Diseases, The Children’s Memorial Health Institute, W 04-730 Warsaw, Poland;
| | - Stephanie Grunewald
- NIHR Biomedical Research Center (BRC), Metabolic Unit, Great Ormond Street Hospital and Institute of Child Health, University College London, London SE1 9RT, UK;
| |
Collapse
|
25
|
Castiglioni C, Feillet F, Barnerias C, Wiedemann A, Muchart J, Cortes F, Hernando-Davalillo C, Montero R, Dupré T, Bruneel A, Seta N, Vuillaumier-Barrot S, Serrano M. Expanding the phenotype of X-linked SSR4-CDG: Connective tissue implications. Hum Mutat 2020; 42:142-149. [PMID: 33300232 DOI: 10.1002/humu.24151] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 11/07/2020] [Accepted: 12/04/2020] [Indexed: 02/01/2023]
Abstract
Signal sequence receptor protein 4 (SSR4) is a subunit of the translocon-associated protein complex, which participates in the translocation of proteins across the endoplasmic reticulum membrane, enhancing the efficiency of N-linked glycosylation. Pathogenic variants in SSR4 cause a congenital disorder of glycosylation: SSR4-congenital disorders of glycosylation (CDG). We describe three SSR4-CDG boys and review the previously reported. All subjects presented with hypotonia, failure to thrive, developmental delay, and dysmorphic traits and showed a type 1 serum sialotransferrin profile, facilitating the diagnosis. Genetic confirmation of this X-linked CDG revealed one de novo hemizygous deletion, one maternally inherited deletion, and one de novo nonsense mutation of SSR4. The present subjects highlight the similarities with a connective tissue disorder (redundant skin, joint laxity, blue sclerae, and vascular tortuosity). The connective tissue problems are relevant, and require preventive rehabilitation measures. As an X-linked disorder, genetic counseling is essential.
Collapse
Affiliation(s)
- Claudia Castiglioni
- Department of Pediatric Neurology, Rare Disease Center, Clínica Las Condes, Santiago, Chile
| | - François Feillet
- Department of Pediatrics, Reference Center for Inborn Errors of Metabolism, University Hospital of Nancy, Nancy, France.,INSERM UMR_S 1256, Nutrition, Genetics, and Environmental Risk Exposure (NGERE), Faculty of Medicine of Nancy, University of Lorraine, Nancy, France
| | - Christine Barnerias
- Pediatric Neurology Department, Center de Référence Maladies Neuromusculaires (GNMH), Necker University Hospital, AP-HP, Paris, France
| | - Arnaud Wiedemann
- Department of Pediatrics, Reference Center for Inborn Errors of Metabolism, University Hospital of Nancy, Nancy, France.,INSERM UMR_S 1256, Nutrition, Genetics, and Environmental Risk Exposure (NGERE), Faculty of Medicine of Nancy, University of Lorraine, Nancy, France
| | - Jordi Muchart
- Department of Radiology, Hospital Sant Joan de Déu, Institut de Recerca Sant Joan de Déu, Barcelona, Spain
| | - Fanny Cortes
- Pediatric Department. Rare Diseases Center, Clínica Las Condes, Santiago, Chile
| | - Cristina Hernando-Davalillo
- Department of Genetic and Molecular Medicine and Pediatric Institute of Rare Diseases, Hospital Sant Joan de Déu, Barcelona, Spain
| | - Raquel Montero
- Clinical Biochemistry Department, Institut de Recerca Hospital Sant Joan de Déu Barcelona, Barcelona, Spain.,Unit-703 Center for Biomedical Research on Rare Diseases (CIBER-ER), Instituto de Salud Carlos III, Madrid, Spain
| | - Thierry Dupré
- Service de Biochimie Métabolique et Cellulaire, Hôpital Bichat-Claude Bernard, AP-HP, Paris, France.,INSERM UMR_S 1149, Faculté de Médecine Xavier Bichat, Université de Paris, Paris, France
| | - Arnaud Bruneel
- Service de Biochimie Métabolique et Cellulaire, Hôpital Bichat-Claude Bernard, AP-HP, Paris, France.,INSERM UMR1193, "Mécanismes cellulaires et moléculaires de l'adaptation au stress et cancérogenèse", Université Paris-Sud, Châtenay-Malabry, France
| | - Nathalie Seta
- Service de Biochimie Métabolique et Cellulaire, Hôpital Bichat-Claude Bernard, AP-HP, Paris, France
| | | | - Mercedes Serrano
- Unit-703 Center for Biomedical Research on Rare Diseases (CIBER-ER), Instituto de Salud Carlos III, Madrid, Spain.,Pediatric Neurology Department, Hospital Sant Joan de Déu, Institut de Recerca Sant Joan de Déu, Barcelona, Spain
| |
Collapse
|
26
|
Castello MA, Gleeson JG. Insight into developmental mechanisms of global and focal migration disorders of cortical development. Curr Opin Neurobiol 2020; 66:77-84. [PMID: 33099181 DOI: 10.1016/j.conb.2020.10.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 10/02/2020] [Accepted: 10/05/2020] [Indexed: 12/20/2022]
Abstract
Cortical development involves neurogenesis followed by migration, maturation, and myelination of immature neurons. Disruptions in these processes can cause malformations of cortical development (MCD). Radial glia (RG) are the stem cells of the brain, both generating neurons and providing the scaffold upon which immature neurons radially migrate. Germline mutations in genes required for cell migration, or cell-cell contact, often lead to global MCDs. Somatic mutations in RG in genes involved in homeostatic function, like mTOR signaling, often lead to focal MCDs. Two different mutations occurring in the same patient can combine in ways we are just beginning to understand. Our growing knowledge about MCD suggests mTOR inhibitors may have expanded utility in treatment-resistant epilepsy, while imaging techniques can better delineate the type and extent of these lesions.
Collapse
Affiliation(s)
- Michael A Castello
- Department of Neurosciences, Division of Child Neurology, University of California San Diego, San Diego, CA, USA
| | - Joseph G Gleeson
- Department of Neurosciences, Rady Children's Institute for Genomic Medicine, University of California San Diego, San Diego, CA, USA.
| |
Collapse
|
27
|
Cao X, Wolf A, Kim SE, Cabrera RM, Wlodarczyk BJ, Zhu H, Parker M, Lin Y, Steele JW, Han X, Ramaekers VT, Steinfeld R, Finnell RH, Lei Y. CIC de novo loss of function variants contribute to cerebral folate deficiency by downregulating FOLR1 expression. J Med Genet 2020; 58:484-494. [PMID: 32820034 PMCID: PMC7895856 DOI: 10.1136/jmedgenet-2020-106987] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 05/27/2020] [Accepted: 06/05/2020] [Indexed: 01/09/2023]
Abstract
Background Cerebral folate deficiency (CFD) syndrome is characterised by a low concentration of 5-methyltetrahydrofolate in cerebrospinal fluid, while folate levels in plasma and red blood cells are in the low normal range. Mutations in several folate pathway genes, including FOLR1 (folate receptor alpha, FRα), DHFR (dihydrofolate reductase) and PCFT (proton coupled folate transporter) have been previously identified in patients with CFD. Methods In an effort to identify causal mutations for CFD, we performed whole exome sequencing analysis on eight CFD trios and identified eight de novo mutations in seven trios. Results Notably, we found a de novo stop gain mutation in the capicua (CIC) gene. Using 48 sporadic CFD samples as a validation cohort, we identified three additional rare variants in CIC that are putatively deleterious mutations. Functional analysis indicates that CIC binds to an octameric sequence in the promoter regions of folate transport genes: FOLR1, PCFT and reduced folate carrier (Slc19A1; RFC1). The CIC nonsense variant (p.R353X) downregulated FOLR1 expression in HeLa cells as well as in the induced pluripotent stem cell (iPSCs) derived from the original CFD proband. Folate binding assay demonstrated that the p.R353X variant decreased cellular binding of folic acid in cells. Conclusion This study indicates that CIC loss of function variants can contribute to the genetic aetiology of CFD through regulating FOLR1 expression. Our study described the first mutations in a non-folate pathway gene that can contribute to the aetiology of CFD.
Collapse
Affiliation(s)
- Xuanye Cao
- Center for Precision Environmental Health, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Annika Wolf
- Department of Pediatric Neurology, University Medical Center Göttingen, Gottingen, Niedersachsen, Germany
| | - Sung-Eun Kim
- Department of Pediatrics, University of Texas at Austin, Austin, Texas, USA
| | - Robert M Cabrera
- Center for Precision Environmental Health, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Bogdan J Wlodarczyk
- Center for Precision Environmental Health, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Huiping Zhu
- Department of Nutritional Sciences, University of Texas at Austin Dell Medical School, Austin, Texas, USA
| | - Margaret Parker
- Department of Pediatrics, University of Texas at Austin, Austin, Texas, USA
| | - Ying Lin
- Center for Precision Environmental Health, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - John W Steele
- Center for Precision Environmental Health, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA.,Institute for Cell and Molecular Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Xiao Han
- Center for Precision Environmental Health, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Vincent Th Ramaekers
- Department of Pediatric Neurology, University Hospital Center Liège, Liège, Belgium
| | - Robert Steinfeld
- Department of Pediatric Neurology, University Medical Center Göttingen, Gottingen, Niedersachsen, Germany .,University Children's Hospital Zurich, Zurich, Switzerland
| | - Richard H Finnell
- Department of Pediatrics, University of Texas at Austin, Austin, Texas, USA .,Center for Precision Environmental Health, Departments of Molecular and Cellular Biology and Medicine, Houston, Texas, USA.,Departments of Molecular and Human Genetics and Medicine, Baylor College of Medicine, Houston, Texas, USA
| | - Yunping Lei
- Center for Precision Environmental Health, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
| |
Collapse
|
28
|
Vaes L, Tiller GE, Pérez B, Boyer SW, Berry SA, Sarafoglou K, Morava E. PMM2-CDG caused by uniparental disomy: Case report and literature review. JIMD Rep 2020; 54:16-21. [PMID: 32685345 PMCID: PMC7358672 DOI: 10.1002/jmd2.12122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 04/01/2020] [Accepted: 04/06/2020] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Phosphomannomutase 2 deficiency (PMM2-CDG) affects glycosylation pathways such as the N-glycosylation pathway, resulting in loss of function of multiple proteins. This disorder causes multisystem involvement with a high variability among patients. PMM2-CDG is an autosomal recessive disorder, which can be caused by inheriting two pathogenic variants, de novo mutations or uniparental disomy. CASE PRESENTATION Our patient presented with multisystem symptoms at an early age including developmental delay, ataxia, and seizures. No diagnosis was obtained till the age of 31 years, when genetic testing was reinitiated. The patient was diagnosed with a complete maternal mixed hetero/isodisomy of chromosome 16, with a homozygous pathogenic PMM2 variant (p.Phe119Leu) causing PMM2-CDG.A literature review revealed eight cases of uniparental disomy as an underlying cause of CDG, four of which are PMM2-CDG. CONCLUSION Since the incidence of homozygosity for PMM2 variants is rare, we suggest further investigations for every homozygous PMM2-CDG patient where the segregation does not fit. These investigations include testing for UPD or a deletion in one of the two alleles, as this will have an impact on recurrence risk in genetic counseling.
Collapse
Affiliation(s)
| | | | - Belén Pérez
- Center of Molecular Biology‐Severo OchoaUniversity Autonomous of Madrid, La Paz Institute for Health Research, Center for Biomedical Research on Rare DiseasesMadridSpain
| | | | - Susan A. Berry
- Division of Genetics and Metabolism, Department of PediatricsUniversity of Minnesota Medical SchoolMinneapolisMinnesotaUSA
| | - Kyriakie Sarafoglou
- Department of PediatricsUniversity of Minnesota Masonic Children's HospitalMinneapolisMinnesotaUSA
| | - Eva Morava
- Department of Clinical Genomics, and Department of Laboratory Medicine and PathologyMayo ClinicRochesterMinnesotaUSA
| |
Collapse
|
29
|
Miller KE, Koboldt DC, Schieffer KM, Bedrosian TA, Crist E, Sheline A, Leraas K, Magrini V, Zhong H, Brennan P, Bush J, Fitch J, Bir N, Miller AR, Cottrell CE, Leonard J, Pindrik JA, Rusin JA, Shah SH, White P, Wilson RK, Mardis ER, Pierson CR, Ostendorf AP. Somatic SLC35A2 mosaicism correlates with clinical findings in epilepsy brain tissue. NEUROLOGY-GENETICS 2020; 6:e460. [PMID: 32637635 PMCID: PMC7323482 DOI: 10.1212/nxg.0000000000000460] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 05/05/2020] [Indexed: 12/30/2022]
Abstract
Objective Many genetic studies of intractable epilepsy in pediatric patients primarily focus on inherited, constitutional genetic deficiencies identified in patient blood. Recently, studies have revealed somatic mosaicism associated with epilepsy in which genetic variants are present only in a subset of brain cells. We hypothesize that tissue-specific, somatic mosaicism represents an important genetic etiology in epilepsy and aim to discover somatic alterations in epilepsy-affected brain tissue. Methods We have pursued a research study to identify brain somatic mosaicism, using next-generation sequencing (NGS) technologies, in patients with treatment refractory epilepsy who have undergone surgical resection of affected brain tissue. Results We used an integrated combination of NGS techniques and conventional approaches (radiology, histopathology, and electrophysiology) to comprehensively characterize multiple brain regions from a single patient with intractable epilepsy. We present a 3-year-old male patient with West syndrome and intractable tonic seizures in whom we identified a pathogenic frameshift somatic variant in SLC35A2, present at a range of variant allele fractions (4.2%–19.5%) in 12 different brain tissues detected by targeted sequencing. The proportion of the SLC35A2 variant correlated with severity and location of neurophysiology and neuroimaging abnormalities for each tissue. Conclusions Our findings support the importance of tissue-based sequencing and highlight a correlation in our patient between SLC35A2 variant allele fractions and the severity of epileptogenic phenotypes in different brain tissues obtained from a grid-based resection of clinically defined epileptogenic regions.
Collapse
Affiliation(s)
- Katherine E Miller
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Daniel C Koboldt
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Kathleen M Schieffer
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Tracy A Bedrosian
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Erin Crist
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Adrienne Sheline
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Kristen Leraas
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Vincent Magrini
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Huachun Zhong
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Patrick Brennan
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Jocelyn Bush
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - James Fitch
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Natalie Bir
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Anthony R Miller
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Catherine E Cottrell
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Jeffrey Leonard
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Jonathan A Pindrik
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Jerome A Rusin
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Summit H Shah
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Peter White
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Richard K Wilson
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Elaine R Mardis
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Christopher R Pierson
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| | - Adam P Ostendorf
- The Steve and Cindy Rasmussen Institute for Genomic Medicine (K.E.M., D.C.K., K.M.S., T.A.B., E.C., K.L., V.M., H.Z., P.B., J.B., J.F., N.B., A.R.M., C.E.C., P.W., R.K.W., E.R.M.), Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH; Division of Genetic and Genomic Medicine (E.C.), Nationwide Children's Hospital, Columbus, OH; Department of Neurosurgery (A.S., J.L., J.A.P.), Nationwide Children's Hospital, Columbus, OH; Department of Pathology and Laboratory Medicine (C.R.P.), Nationwide Children's Hospital, Columbus, OH; Division of Child Neurology (A.P.O.), Nationwide Children's Hospital, Columbus, OH; Department of Radiology (J.A.R., S.H.S), Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics (D.C.K., V.M., C.E.C., J.L., P.W., R.K.W, E.R.M., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Neurosurgery (J.L., J.A.P., A.P.O.), The Ohio State University College of Medicine, Columbus, OH; Department of Pathology (C.E.C., C.R.P.), The Ohio State University College of Medicine, Columbus, OH; and Department of Biomedical Education & Anatomy (C.R.P.), Division of Anatomy, The Ohio State University College of Medicine, Columbus, OH
| |
Collapse
|
30
|
Heinzen EL. Somatic variants in epilepsy - advancing gene discovery and disease mechanisms. Curr Opin Genet Dev 2020; 65:1-7. [PMID: 32422520 DOI: 10.1016/j.gde.2020.04.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 04/15/2020] [Indexed: 01/03/2023]
Abstract
In the past ten years, there has been increasing recognition that cells can acquire genetic variants during cortical development that can give rise to brain malformations as well as nonlesional focal epilepsy. These often brain tissue-specific, de novo variants can result in highly variable phenotypes based on the burden of a variant in specific tissues and cells. By discovering these variants, shared pathophysiological mechanisms are being revealed between clinically distinct disorders. Beyond informing disease mechanisms, mosaic variants also offer a powerful research tool to trace cellular lineages, to study the roles of specialized cell types in disease presentation, and to establish the cell-type specific genomic consequences of a variant.
Collapse
Affiliation(s)
- Erin L Heinzen
- Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina, Chapel Hill, NC, United States; Department of Genetics, School of Medicine, University of North Carolina, Chapel Hill, NC, United States.
| |
Collapse
|
31
|
Abstract
PURPOSE OF REVIEW Although differentiating neonatal-onset epilepsies from acute symptomatic neonatal seizures has been increasingly recognized as crucial, existing guidelines, and recommendations on EEG monitoring are mainly based on acute symptomatic seizures, especially secondary to hypoxic-ischemic encephalopathy. We aimed to narratively review current knowledge on neonatal-onset epilepsies of genetic, metabolic, and structural non-acquired origin, with special emphasis on EEG features and monitoring. RECENT FINDINGS A wide range of rare conditions are increasingly described, reducing undiagnosed cases. Although distinguishing features are identifiable in some, how to best monitor and detect less described etiologies is still an issue. A comprehensive approach considering onset, seizure evolution, ictal semiology, clinical, laboratory, EEG, and neuroimaging data is key to diagnosis. Phenotypic variability prevents precise recommendations, but a solid, consistent method moving from existing published guidelines helps in correctly assessing these newborns in order to provide better care, especially in view of expanding precision therapies.
Collapse
|
32
|
Li D, Mukhopadhyay S. Functional analyses of the UDP-galactose transporter SLC35A2 using the binding of bacterial Shiga toxins as a novel activity assay. Glycobiology 2020; 29:490-503. [PMID: 30834435 DOI: 10.1093/glycob/cwz016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/17/2019] [Accepted: 02/28/2019] [Indexed: 01/13/2023] Open
Abstract
SLC35A2 transports UDP-galactose from the cytosol to the lumen of the Golgi apparatus and endoplasmic reticulum for glycosylation. Mutations in SLC35A2 induce a congenital disorder of glycosylation. Despite the biomedical relevance, mechanisms of transport via SLC35A2 and the impact of disease-associated mutations on activity are unclear. To address these issues, we generated a predicted structure of SLC35A2 and assayed for the effects of a set of structural and disease-associated mutations. Activity assays were performed using a rescue approach in ΔSLC35A2 cells and took advantage of the fact that SLC35A2 is required for expression of the glycosphingolipid globotriaosylceramide (Gb3), the cell surface receptor for Shiga toxin 1 (STx1) and 2 (STx2). The N- and C-terminal cytoplasmic loops of SLC35A2 were dispensable for activity, but two critical glycine (Gly-202 and Gly-214) and lysine (Lys-78 and Lys-297) residues in transmembrane segments were required. Residues corresponding to Gly-202 and Gly-214 in the related transporter SLC35A1 form a substrate-translocating channel, suggesting that a similar mechanism may be involved in SLC35A2. Among the eight disease-associated mutations tested, SLC35A2 function was completely inhibited by two (S213F and G282R) and partially inhibited by three (R55L, G266V, and S304P), providing a straight-forward mechanism of disease. Interestingly, the remaining three (V331I, V258M, and Y267C) did not impact SLC35A2 function, suggesting that complexities beyond loss of transporter activity may underlie disease due to these mutations. Overall, our results provide new insights into the mechanisms of transport of SLC35A2 and improve understanding of the relationship between SLC35A2 mutations and disease.
Collapse
Affiliation(s)
- Danyang Li
- Division of Pharmacology & Toxicology, College of Pharmacy, Institute for Cellular & Molecular Biology, and Institute for Neuroscience, The University of Texas at Austin, Austin, TX, USA
| | - Somshuvra Mukhopadhyay
- Division of Pharmacology & Toxicology, College of Pharmacy, Institute for Cellular & Molecular Biology, and Institute for Neuroscience, The University of Texas at Austin, Austin, TX, USA
| |
Collapse
|
33
|
Miyamoto S, Nakashima M, Ohashi T, Hiraide T, Kurosawa K, Yamamoto T, Takanashi J, Osaka H, Inoue K, Miyazaki T, Wada Y, Okamoto N, Saitsu H. A case of de novo splice site variant in SLC35A2 showing developmental delays, spastic paraplegia, and delayed myelination. Mol Genet Genomic Med 2019; 7:e814. [PMID: 31231989 PMCID: PMC6687661 DOI: 10.1002/mgg3.814] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 05/30/2019] [Accepted: 05/31/2019] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Congenital disorders of glycosylation (CDGs) are genetic diseases caused by pathogenic variants of genes involved in protein or lipid glycosylation. De novo variants in the SLC35A2 gene, which encodes a UDP-galactose transporter, are responsible for CDGs with an X-linked dominant manner. Common symptoms related to SLC35A2 variants include epilepsy, psychomotor developmental delay, hypotonia, abnormal facial and skeletal features, and various magnetic resonance imaging (MRI) findings. METHODS Whole-exome sequencing was performed on the patient's DNA, and candidate variants were confirmed by Sanger sequencing. cDNA analysis was performed to assess the effect of the splice site variant using peripheral leukocytes. The X-chromosome inactivation pattern was studied using the human androgen receptor assay. RESULTS We identified a de novo splice site variant in SLC35A2 (NM_005660.2: c.274+1G>A) in a female patient who showed severe developmental delay, spastic paraplegia, mild cerebral atrophy, and delayed myelination on MRI, but no seizures. The variant led to an aberrant splicing resulting in an in-frame 33-bp insertion, which caused an 11-amino acid insertion in the presumptive cytoplasmic loop. X-inactivation pattern was random. Partial loss of galactose and sialic acid of the N-linked glycans of serum transferrin was observed. CONCLUSION This case would expand the phenotypic spectrum of SLC35A2-related disorders to delayed myelination with spasticity and no seizures.
Collapse
Affiliation(s)
- Sachiko Miyamoto
- Department of BiochemistryHamamatsu University School of MedicineHamamatsuJapan
| | - Mitsuko Nakashima
- Department of BiochemistryHamamatsu University School of MedicineHamamatsuJapan
| | - Tsukasa Ohashi
- Department of PediatricsNiigata University Medical and Dental HospitalNiigataJapan
| | - Takuya Hiraide
- Department of BiochemistryHamamatsu University School of MedicineHamamatsuJapan
| | - Kenji Kurosawa
- Division of Medical GeneticsKanagawa Children's Medical CenterYokohamaJapan
| | - Toshiyuki Yamamoto
- Tokyo Women's Medical University Institute for Integrated Medical SciencesTokyoJapan
| | - Junichi Takanashi
- Department of Pediatrics and Pediatric NeurologyTokyo Women's Medical University, Yachiyo Medical CenterYachiyoJapan
| | - Hitoshi Osaka
- Department of PediatricsJichi Medical UniversityTochigiJapan
| | - Ken Inoue
- Department of Mental Retardation & Birth Defect ResearchNational Institute of NeuroscienceNational Center of Neurology & PsychiatryJapan
| | - Takehiro Miyazaki
- Department of BiochemistryHamamatsu University School of MedicineHamamatsuJapan
| | - Yoshinao Wada
- Department of Molecular MedicineOsaka Women's and Children's HospitalOsakaJapan
| | - Nobuhiko Okamoto
- Department of Molecular MedicineOsaka Women's and Children's HospitalOsakaJapan
- Department of Medical GeneticsOsaka Women's and Children's HospitalOsakaJapan
| | - Hirotomo Saitsu
- Department of BiochemistryHamamatsu University School of MedicineHamamatsuJapan
| |
Collapse
|
34
|
Ye Z, McQuillan L, Poduri A, Green TE, Matsumoto N, Mefford HC, Scheffer IE, Berkovic SF, Hildebrand MS. Somatic mutation: The hidden genetics of brain malformations and focal epilepsies. Epilepsy Res 2019; 155:106161. [PMID: 31295639 DOI: 10.1016/j.eplepsyres.2019.106161] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 06/27/2019] [Accepted: 07/01/2019] [Indexed: 01/12/2023]
Abstract
Over the past decade there has been a substantial increase in genetic studies of brain malformations, fueled by the availability of improved technologies to study surgical tissue to address the hypothesis that focal lesions arise from focal, post-zygotic genetic disruptions. Traditional genetic studies of patients with malformations utilized leukocyte-derived DNA to search for germline variants, which are inherited or arise de novo in parental gametes. Recent studies have demonstrated somatic variants that arise post-zygotically also underlie brain malformations, and that somatic mutation explains a larger proportion of focal malformations than previously thought. We now know from studies of non-diseased individuals that somatic variation occurs routinely during cell division, including during early brain development when the rapid proliferation of neuronal precursor cells provides the ideal environment for somatic mutation to occur and somatic variants to accumulate. When confined to brain, pathogenic variants contribute to the "hidden genetics" of neurological diseases. With burgeoning novel high-throughput genetic technologies, somatic genetic variations are increasingly being recognized. Here we discuss accumulating evidence for the presence of somatic variants in normal brain tissue, review our current understanding of somatic variants in brain malformations associated with lesional epilepsy, and provide strategies to identify the potential contribution of somatic mutation to non-lesional epilepsies. We also discuss technologies that may improve detection of somatic variants in the future in these and other neurological conditions.
Collapse
Affiliation(s)
- Zimeng Ye
- Department of Medicine (Austin Hospital), University of Melbourne, Heidelberg, Victoria, Australia
| | - Lara McQuillan
- Department of Medicine (Austin Hospital), University of Melbourne, Heidelberg, Victoria, Australia
| | - Annapurna Poduri
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, and Department of Neurology, Harvard Medical School, Boston, MA, United States
| | - Timothy E Green
- Department of Medicine (Austin Hospital), University of Melbourne, Heidelberg, Victoria, Australia
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Heather C Mefford
- Division of Genetic Medicine, Department of Pediatrics, University of Washington and Seattle Children's Hospital, Seattle, WA, United States
| | - Ingrid E Scheffer
- Department of Medicine (Austin Hospital), University of Melbourne, Heidelberg, Victoria, Australia; Department of Pediatrics, University of Melbourne, Royal Children's Hospital, Parkville, Victoria, Australia; Department of Neurology, Royal Children's Hospital, Parkville, Victoria, Australia; Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Samuel F Berkovic
- Department of Medicine (Austin Hospital), University of Melbourne, Heidelberg, Victoria, Australia
| | - Michael S Hildebrand
- Department of Medicine (Austin Hospital), University of Melbourne, Heidelberg, Victoria, Australia; Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia.
| |
Collapse
|
35
|
Ng BG, Sosicka P, Agadi S, Almannai M, Bacino CA, Barone R, Botto LD, Burton JE, Carlston C, Hon-Yin Chung B, Cohen JS, Coman D, Dipple KM, Dorrani N, Dobyns WB, Elias AF, Epstein L, Gahl WA, Garozzo D, Hammer TB, Haven J, Héron D, Herzog M, Hoganson GE, Hunter JM, Jain M, Juusola J, Lakhani S, Lee H, Lee J, Lewis K, Longo N, Lourenço CM, Mak CC, McKnight D, Mendelsohn BA, Mignot C, Mirzaa G, Mitchell W, Muhle H, Nelson SF, Olczak M, Palmer CG, Partikian A, Patterson MC, Pierson TM, Quinonez SC, Regan BM, Ross ME, Guillen Sacoto MJ, Scaglia F, Scheffer IE, Segal D, Shah Singhal N, Striano P, Sturiale L, Symonds JD, Tang S, Vilain E, Willis M, Wolfe LA, Yang H, Yano S, Powis Z, Suchy SF, Rosenfeld JA, Edmondson AC, Grunewald S, Freeze HH. SLC35A2-CDG: Functional characterization, expanded molecular, clinical, and biochemical phenotypes of 30 unreported Individuals. Hum Mutat 2019; 40:908-925. [PMID: 30817854 PMCID: PMC6661012 DOI: 10.1002/humu.23731] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 02/11/2019] [Accepted: 02/20/2019] [Indexed: 12/15/2022]
Abstract
Pathogenic de novo variants in the X-linked gene SLC35A2 encoding the major Golgi-localized UDP-galactose transporter required for proper protein and lipid glycosylation cause a rare type of congenital disorder of glycosylation known as SLC35A2-congenital disorders of glycosylation (CDG; formerly CDG-IIm). To date, 29 unique de novo variants from 32 unrelated individuals have been described in the literature. The majority of affected individuals are primarily characterized by varying degrees of neurological impairments with or without skeletal abnormalities. Surprisingly, most affected individuals do not show abnormalities in serum transferrin N-glycosylation, a common biomarker for most types of CDG. Here we present data characterizing 30 individuals and add 26 new variants, the single largest study involving SLC35A2-CDG. The great majority of these individuals had normal transferrin glycosylation. In addition, expanding the molecular and clinical spectrum of this rare disorder, we developed a robust and reliable biochemical assay to assess SLC35A2-dependent UDP-galactose transport activity in primary fibroblasts. Finally, we show that transport activity is directly correlated to the ratio of wild-type to mutant alleles in fibroblasts from affected individuals.
Collapse
Affiliation(s)
- Bobby G. Ng
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California
| | - Paulina Sosicka
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California
| | - Satish Agadi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Mohammed Almannai
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Carlos A. Bacino
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
- Texas Children’s Hospital, Houston, Texas
| | - Rita Barone
- Child Neurology and Psychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania - Italy
- CNR, Institute for Polymers, Composites and Biomaterials, Catania, Italy
| | - Lorenzo D. Botto
- Division of Medical Genetics, Departments of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Jennifer E. Burton
- Department of Pediatrics, University of Illinois College of Medicine, Peoria, Illinois
| | - Colleen Carlston
- Department of Pathology, University of Utah, Salt Lake City, Utah
| | - Brian Hon-Yin Chung
- Department of Paediatrics & Adolescent Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR China
| | - Julie S. Cohen
- Division of Neurogenetics and Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, Maryland
| | - David Coman
- Department of Metabolic Medicine, Queensland Children’s Hospital, Brisbane, Australia
- Schools of Medicine, University of Queensland Brisbane, Griffith University Gold Coast, Brisbane, Australia
| | - Katrina M. Dipple
- Department of Pediatrics, University of Washington, Seattle WA
- Seattle Children’s Hospital, Seattle WA
- Department of Human Genetics, UCLA, Los Angeles CA
| | | | - William B. Dobyns
- Departments of Pediatrics, University of Washington, Seattle, Washington
- Center for Integrative Brain Research, Seattle Children’s Research Institute, Seattle, Washington
| | - Abdallah F. Elias
- Department of Medical Genetics, Shodair Children’s Hospital, PO Box 5539, Helena, Montana
| | - Leon Epstein
- Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - William A. Gahl
- Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
- Undiagnosed Diseases program, Common Fund, National Institutes of Health, Bethesda, Maryland
| | - Domenico Garozzo
- CNR, Institute for Polymers, Composites and Biomaterials, Catania, Italy
| | | | - Jaclyn Haven
- Department of Medical Genetics, Shodair Children’s Hospital, PO Box 5539, Helena, Montana
| | - Delphine Héron
- APHP, Département de Génétique, GH Pitié Salpêtrière, CRMR Déficiences Intellectuelles de Causes Rares, Sorbonne Université GRC 9, Paris, France
| | | | - George E. Hoganson
- Department of Pediatrics, University of Illinois College of Medicine, Peoria, Illinois
| | | | - Mahim Jain
- Division of Neurogenetics and Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, Maryland
| | | | - Shenela Lakhani
- Center for Neurogenetics Brain and Mind Research Institute Weill Cornell Medicine New York, NY
| | - Hane Lee
- Department of Human Genetics, UCLA, Los Angeles CA
- Department of Pathology and Laboratory Medicine, UCLA, Los Angeles, CA
| | - Joy Lee
- Department of Metabolic Medicine, The Royal Children’s Hospital, Melbourne, Parkville, Victoria, Australia
- Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia
| | - Katherine Lewis
- Department of Metabolic Medicine, Queensland Children’s Hospital, Brisbane, Australia
| | - Nicola Longo
- Division of Medical Genetics, Departments of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Charles Marques Lourenço
- Clinical Genetics and Neurogenetics, Centro Universitario Estacio de Ribeirao Preto, Ribeirao Preto, Brazil
| | - Christopher C.Y. Mak
- Department of Paediatrics & Adolescent Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR China
| | | | - Bryce A. Mendelsohn
- Department of Pediatrics, Division of Medical Genetics, University of California, San Francisco, San Francisco, California
| | - Cyril Mignot
- APHP, Département de Génétique, GH Pitié Salpêtrière, CRMR Déficiences Intellectuelles de Causes Rares, Sorbonne Université GRC 9, Paris, France
| | - Ghayda Mirzaa
- Departments of Pediatrics, University of Washington, Seattle, Washington
- Center for Integrative Brain Research, Seattle Children’s Research Institute, Seattle, Washington
| | - Wendy Mitchell
- Neurology Division Children’s Hospital Los Angeles, Los Angeles, California
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Hiltrud Muhle
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Stanley F. Nelson
- Department of Human Genetics, UCLA, Los Angeles CA
- Department of Pathology and Laboratory Medicine, UCLA, Los Angeles, CA
- Department of Psychiatry & Biobehavioral Sciences, UCLA, Los Angeles, CA
| | - Mariusz Olczak
- Laboratory of Biochemistry, Faculty of Biotechnology, University of Wroclaw, 14A F. Joliot-Curie St., 50-383 Wroclaw, Poland
| | - Christina G.S. Palmer
- Department of Human Genetics, UCLA, Los Angeles CA
- Department of Psychiatry & Biobehavioral Sciences, UCLA, Los Angeles, CA
- Institute for Society and Genetics, UCLA, Los Angeles, CA
| | - Arthur Partikian
- Departments of Pediatrics & Neurology, Keck School of Medicine of University of Southern California, Los Angeles, California
| | - Marc C. Patterson
- Division of Child and Adolescent Neurology, Mayo Clinic, Rochester, Minnesota
| | - Tyler M. Pierson
- Department of Pediatrics, Cedars-Sinai Medical Center, Los Angeles, California
- Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California
| | - Shane C. Quinonez
- Department of Pediatrics, Division of Genetics, Metabolism and Genomic Medicine, University of Michigan, Ann Arbor, Michigan
| | - Brigid M. Regan
- The University of Melbourne, Austin Health, Melbourne, Australia
| | - M. Elizabeth Ross
- Center for Neurogenetics Brain and Mind Research Institute Weill Cornell Medicine New York, NY
| | | | - Fernando Scaglia
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
- Texas Children’s Hospital, Houston, Texas
- Joint BCM-CUHK Center of Medical Genetics, Prince of Wales Hospital, ShaTin, Hong Kong SAR
| | - Ingrid E. Scheffer
- The University of Melbourne, Austin Health, Melbourne, Australia
- The University of Melbourne, Royal Children’s Hospital, Florey Institute and Murdoch Children’s Research Institute, Melbourne, Australia
| | - Devorah Segal
- Center for Neurogenetics Brain and Mind Research Institute Weill Cornell Medicine New York, NY
- Department of Pediatrics Division of Child Neurology Weill Cornell Medicine New York, New York
| | - Nilika Shah Singhal
- Neurology & Pediatrics, University of California, San Francisco, San Francisco, California
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, “G. Gaslini” Institute, Genova, Italy
| | - Luisa Sturiale
- CNR, Institute for Polymers, Composites and Biomaterials, Catania, Italy
| | - Joseph D. Symonds
- Paediatric Neurosciences Research Group, Royal Hospital for Children, Queen Elizabeth University Hospitals, 1345 Govan Road, Glasgow, G51 4TF, UK
| | - Sha Tang
- Ambry Genetics, Aliso Viejo, California
| | - Eric Vilain
- Center for Genetic Medicine Research, Children’s National Medical Center, Washington, District of Columbia
| | - Mary Willis
- Department of Pediatrics, Naval Medical Center, San Diego, California
| | - Lynne A. Wolfe
- Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
- Undiagnosed Diseases program, Common Fund, National Institutes of Health, Bethesda, Maryland
| | | | - Shoji Yano
- Genetics Division, Department of Pediatrics, LAC+USC Medical Center, University of Southern California, Los Angeles, California
| | | | - Zöe Powis
- Ambry Genetics, Aliso Viejo, California
| | | | - Jill A. Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Andrew C. Edmondson
- Division of Human Genetics, Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Stephanie Grunewald
- Metabolic Unit, Great Ormond Street Hospital NHS Trust, Institute for Child Health UCL, London/UK
| | - Hudson H. Freeze
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California
| |
Collapse
|
36
|
Toscanini MA, Favarolo MB, Gonzalez Flecha FL, Ebert B, Rautengarten C, Bredeston LM. Conserved Glu-47 and Lys-50 residues are critical for UDP- N-acetylglucosamine/UMP antiport activity of the mouse Golgi-associated transporter Slc35a3. J Biol Chem 2019; 294:10042-10054. [PMID: 31118275 DOI: 10.1074/jbc.ra119.008827] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 05/09/2019] [Indexed: 12/17/2022] Open
Abstract
Nucleotide sugar transporters (NSTs) regulate the flux of activated sugars from the cytosol into the lumen of the Golgi apparatus where glycosyltransferases use them for the modification of proteins, lipids, and proteoglycans. It has been well-established that NSTs are antiporters that exchange nucleotide sugars with the respective nucleoside monophosphate. Nevertheless, information about the molecular basis of ligand recognition and transport is scarce. Here, using topology predictors, cysteine-scanning mutagenesis, expression of GFP-tagged protein variants, and phenotypic complementation of the yeast strain Kl3, we identified residues involved in the activity of a mouse UDP-GlcNAc transporter, murine solute carrier family 35 member A3 (mSlc35a3). We specifically focused on the putative transmembrane helix 2 (TMH2) and observed that cells expressing E47C or K50C mSlc35a3 variants had lower levels of GlcNAc-containing glycoconjugates than WT cells, indicating impaired UDP-GlcNAc transport activity of these two variants. A conservative substitution analysis revealed that single or double substitutions of Glu-47 and Lys-50 do not restore GlcNAc glycoconjugates. Analysis of mSlc35a3 and its genetic variants reconstituted into proteoliposomes disclosed the following: (i) all variants act as UDP-GlcNAc/UMP antiporters; (ii) conservative substitutions (E47D, E47Q, K50R, or K50H) impair UDP-GlcNAc uptake; and (iii) substitutions of Glu-47 and Lys-50 dramatically alter kinetic parameters, consistent with a critical role of these two residues in mSlc35a3 function. A bioinformatics analysis revealed that an EXXK motif in TMH2 is highly conserved across SLC35 A subfamily members, and a 3D-homology model predicted that Glu-47 and Lys-50 are facing the central cavity of the protein.
Collapse
Affiliation(s)
- M Agustina Toscanini
- From the Departamento de Química Biológica-IQUIFIB, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires-CONICET, Ciudad Autónoma de Buenos Aires, Junín 956 (1113), Argentina and
| | - M Belén Favarolo
- From the Departamento de Química Biológica-IQUIFIB, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires-CONICET, Ciudad Autónoma de Buenos Aires, Junín 956 (1113), Argentina and
| | - F Luis Gonzalez Flecha
- From the Departamento de Química Biológica-IQUIFIB, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires-CONICET, Ciudad Autónoma de Buenos Aires, Junín 956 (1113), Argentina and
| | - Berit Ebert
- the School of BioSciences, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Carsten Rautengarten
- the School of BioSciences, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Luis M Bredeston
- From the Departamento de Química Biológica-IQUIFIB, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires-CONICET, Ciudad Autónoma de Buenos Aires, Junín 956 (1113), Argentina and
| |
Collapse
|
37
|
Vals MA, Ashikov A, Ilves P, Loorits D, Zeng Q, Barone R, Huijben K, Sykut-Cegielska J, Diogo L, Elias AF, Greenwood RS, Grunewald S, van Hasselt PM, van de Kamp JM, Mancini G, Okninska A, Pajusalu S, Rudd PM, Rustad CF, Salvarinova R, de Vries BBA, Wolf NI, Ng BG, Freeze HH, Lefeber DJ, Õunap K. Clinical, neuroradiological, and biochemical features of SLC35A2-CDG patients. J Inherit Metab Dis 2019; 42:553-564. [PMID: 30746764 DOI: 10.1002/jimd.12055] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 11/14/2018] [Accepted: 11/19/2018] [Indexed: 11/10/2022]
Abstract
SLC35A2-CDG is caused by mutations in the X-linked SLC35A2 gene encoding the UDP-galactose transporter. SLC35A2 mutations lead to hypogalactosylation of N-glycans. SLC35A2-CDG is characterized by severe neurological symptoms and, in many patients, early-onset epileptic encephalopathy. In view of the diagnostic challenges, we studied the clinical, neuroradiological, and biochemical features of 15 patients (11 females and 4 males) with SLC35A2-CDG from various centers. We describe nine novel pathogenic variations in SLC35A2. All affected individuals presented with a global developmental delay, and hypotonia, while 70% were nonambulatory. Epilepsy was present in 80% of the patients, and in EEG hypsarrhythmia and findings consistent with epileptic encephalopathy were frequently seen. The most common brain MRI abnormality was cerebral atrophy with delayed myelination and multifocal inhomogeneous abnormal patchy white matter hyperintensities, which seemed to be nonprogressive. Thin corpus callosum was also common, and all the patients had a corpus callosum shorter than normal for their age. Variable dysmorphic features and growth deficiency were noted. Biochemically, normal mucin type O-glycosylation and lipid glycosylation were found, while transferrin mass spectrometry was found to be more specific in the identification of SLC35A2-CDG, as compared to routine screening tests. Although normal glycosylation studies together with clinical variability and genetic results complicate the diagnosis of SLC35A2-CDG, our data indicate that the combination of these three elements can support the pathogenicity of mutations in SLC35A2.
Collapse
Affiliation(s)
- Mari-Anne Vals
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
- Children's Clinic, Tartu University Hospital, Tartu, Estonia
| | - Angel Ashikov
- Donders Institute for Brain, Cognition, and Behavior, Department of Neurology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Pilvi Ilves
- Radiology Clinic, Tartu University Hospital, Tartu, Estonia
- Department of Radiology, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Dagmar Loorits
- Radiology Clinic, Tartu University Hospital, Tartu, Estonia
- Department of Radiology, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Qiang Zeng
- GlycoScience Group, National Institute for Bioprocessing Research & Training, Dublin, Ireland
| | - Rita Barone
- Child Neurology and Psychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
- Department of Clinical and Experimental Medicine, Referral Centre for Inherited Metabolic Diseases, University of Catania, Catania, Italy
| | - Karin Huijben
- Department of Laboratory Medicine, Translational Metabolic Laboratory, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jolanta Sykut-Cegielska
- Department of Inborn Errors of Metabolism and Paediatrics, Institute of Mother and Child, Warsaw, Poland
| | - Luísa Diogo
- Child Developmental Center, Hospital Pediátrico, Center for Inherited Metabolic Diseases, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - Abdallah F Elias
- Department of Medical Genetics, Shodair Children's Hospital, Helena, Montana
| | - Robert S Greenwood
- Department of Neurology, University of North Carolina School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Stephanie Grunewald
- Metabolic Unit, Great Ormond Street Hospital and Institute of Child Health, University College London, NHS Trust, London, UK
| | - Peter M van Hasselt
- Division Pediatrics, Metabolic Diseases, Wilhelmina Children's Hospital (Part of UMC Utrecht), Utrecht, The Netherlands
| | - Jiddeke M van de Kamp
- Department of Clinical Genetics, VU University Medical Center, Amsterdam, The Netherlands
| | - Grazia Mancini
- Department of Clinical Genetics, Erasmus MC University Medical Centre, Rotterdam, The Netherlands
| | - Agnieszka Okninska
- Clinic of Children and Adolescent Neurology, Institute of Mother and Child, Warsaw, Poland
| | - Sander Pajusalu
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Pauline M Rudd
- GlycoScience Group, National Institute for Bioprocessing Research & Training, Dublin, Ireland
| | - Cecilie F Rustad
- Department of Medical Genetics, Oslo University Hospital, Oslo, Norway
| | - Ramona Salvarinova
- Division of Biochemical Diseases, Department of Pediatrics, British Columbia Children's Hospital, UBC BC Children's Hospital Research Institute, Vancouver, Canada
| | - Bert B A de Vries
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Nicole I Wolf
- Department of Child Neurology and Amsterdam Neuroscience, VU University Medical Center, Amsterdam, The Netherlands
| | - Bobby G Ng
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California
| | - Hudson H Freeze
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California
| | - Dirk J Lefeber
- Donders Institute for Brain, Cognition, and Behavior, Department of Neurology, Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Laboratory Medicine, Translational Metabolic Laboratory, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Katrin Õunap
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| |
Collapse
|
38
|
Ahuja S, Whorton MR. Structural basis for mammalian nucleotide sugar transport. eLife 2019; 8:45221. [PMID: 30985278 PMCID: PMC6508934 DOI: 10.7554/elife.45221] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 04/13/2019] [Indexed: 12/12/2022] Open
Abstract
Nucleotide-sugar transporters (NSTs) are critical components of the cellular glycosylation machinery. They transport nucleotide-sugar conjugates into the Golgi lumen, where they are used for the glycosylation of proteins and lipids, and they then subsequently transport the nucleotide monophosphate byproduct back to the cytoplasm. Dysregulation of human NSTs causes several debilitating diseases, and NSTs are virulence factors for many pathogens. Here we present the first crystal structures of a mammalian NST, the mouse CMP-sialic acid transporter (mCST), in complex with its physiological substrates CMP and CMP-sialic acid. Detailed visualization of extensive protein-substrate interactions explains the mechanisms governing substrate selectivity. Further structural analysis of mCST’s unique lumen-facing partially-occluded conformation, coupled with the characterization of substrate-induced quenching of mCST’s intrinsic tryptophan fluorescence, reveals the concerted conformational transitions that occur during substrate transport. These results provide a framework for understanding the effects of disease-causing mutations and the mechanisms of this diverse family of transporters. The cells in our body are tiny machines which, amongst other things, produce proteins. One of the production steps involves a compartment in the cell called the Golgi, where proteins are tagged and packaged before being sent to their final destination. In particular, sugars can be added onto an immature protein to help to fold it, stabilize it, and to affect how it works. Before sugars can be attached to a protein, they need to be ‘activated’ outside of the Golgi by attaching to a small molecule known as a nucleotide. Then, these ‘nucleotide-sugars’ are ferried across the Golgi membrane and inside the compartment by nucleotide-sugar transporters, or NSTs. Humans have seven different kinds of NSTs, each responsible for helping specific types of nucleotide-sugars cross the Golgi membrane. Changes in NSTs are linked to several human diseases, including certain types of epilepsy; these proteins are also important for dangerous microbes to be able to infect cells. Yet, scientists know very little about how the transporters recognize their cargo, and how they transport it. To shed light on these questions, Ahuja and Whorton set to uncover for the first time the 3D structure of a mammalian NST using a method known as X-ray crystallography. This revealed how nearly every component of this transporter is arranged when the protein is bound to two different molecules: a specific nucleotide, or a type of nucleotide-sugar. The results help to understand how changes in certain components of the NST can lead to a problem in the way the protein works. Ultimately, this knowledge may be useful to prevent diseases linked to faulty NSTs, or to stop microbes from using the transporters to their own advantage.
Collapse
Affiliation(s)
- Shivani Ahuja
- Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Matthew R Whorton
- Vollum Institute, Oregon Health & Science University, Portland, United States
| |
Collapse
|
39
|
Meech R, Hu DG, McKinnon RA, Mubarokah SN, Haines AZ, Nair PC, Rowland A, Mackenzie PI. The UDP-Glycosyltransferase (UGT) Superfamily: New Members, New Functions, and Novel Paradigms. Physiol Rev 2019; 99:1153-1222. [DOI: 10.1152/physrev.00058.2017] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
UDP-glycosyltransferases (UGTs) catalyze the covalent addition of sugars to a broad range of lipophilic molecules. This biotransformation plays a critical role in elimination of a broad range of exogenous chemicals and by-products of endogenous metabolism, and also controls the levels and distribution of many endogenous signaling molecules. In mammals, the superfamily comprises four families: UGT1, UGT2, UGT3, and UGT8. UGT1 and UGT2 enzymes have important roles in pharmacology and toxicology including contributing to interindividual differences in drug disposition as well as to cancer risk. These UGTs are highly expressed in organs of detoxification (e.g., liver, kidney, intestine) and can be induced by pathways that sense demand for detoxification and for modulation of endobiotic signaling molecules. The functions of the UGT3 and UGT8 family enzymes have only been characterized relatively recently; these enzymes show different UDP-sugar preferences to that of UGT1 and UGT2 enzymes, and to date, their contributions to drug metabolism appear to be relatively minor. This review summarizes and provides critical analysis of the current state of research into all four families of UGT enzymes. Key areas discussed include the roles of UGTs in drug metabolism, cancer risk, and regulation of signaling, as well as the transcriptional and posttranscriptional control of UGT expression and function. The latter part of this review provides an in-depth analysis of the known and predicted functions of UGT3 and UGT8 enzymes, focused on their likely roles in modulation of levels of endogenous signaling pathways.
Collapse
Affiliation(s)
- Robyn Meech
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University College of Medicine and Public Health, Flinders Medical Centre, Bedford Park, South Australia, Australia
| | - Dong Gui Hu
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University College of Medicine and Public Health, Flinders Medical Centre, Bedford Park, South Australia, Australia
| | - Ross A. McKinnon
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University College of Medicine and Public Health, Flinders Medical Centre, Bedford Park, South Australia, Australia
| | - Siti Nurul Mubarokah
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University College of Medicine and Public Health, Flinders Medical Centre, Bedford Park, South Australia, Australia
| | - Alex Z. Haines
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University College of Medicine and Public Health, Flinders Medical Centre, Bedford Park, South Australia, Australia
| | - Pramod C. Nair
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University College of Medicine and Public Health, Flinders Medical Centre, Bedford Park, South Australia, Australia
| | - Andrew Rowland
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University College of Medicine and Public Health, Flinders Medical Centre, Bedford Park, South Australia, Australia
| | - Peter I. Mackenzie
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University College of Medicine and Public Health, Flinders Medical Centre, Bedford Park, South Australia, Australia
| |
Collapse
|
40
|
Chen J, Li X, Edmondson A, Meyers GD, Izumi K, Ackermann AM, Morava E, Ficicioglu C, Bennett MJ, He M. Increased Clinical Sensitivity and Specificity of Plasma Protein N-Glycan Profiling for Diagnosing Congenital Disorders of Glycosylation by Use of Flow Injection-Electrospray Ionization-Quadrupole Time-of-Flight Mass Spectrometry. Clin Chem 2019; 65:653-663. [PMID: 30770376 DOI: 10.1373/clinchem.2018.296780] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 01/23/2019] [Indexed: 12/27/2022]
Abstract
BACKGROUND Congenital disorders of glycosylation (CDG) represent 1 of the largest groups of metabolic disorders with >130 subtypes identified to date. The majority of CDG subtypes are disorders of N-linked glycosylation, in which carbohydrate residues, namely, N-glycans, are posttranslationally linked to asparagine molecules in peptides. To improve the diagnostic capability for CDG, we developed and validated a plasma N-glycan assay using flow injection-electrospray ionization-quadrupole time-of-flight mass spectrometry. METHODS After PNGase F digestion of plasma glycoproteins, N-glycans were linked to a quinolone using a transient amine group at the reducing end, isolated by a hydrophilic interaction chromatography column, and then identified by accurate mass and quantified using a stable isotope-labeled glycopeptide as the internal standard. RESULTS This assay differed from other N-glycan profiling methods because it was free of any contamination from circulating free glycans and was semiquantitative. The low end of the detection range tested was at 63 nmol/L for disialo-biantennary N-glycan. The majority of N-glycans in normal plasma had <1% abundance. Abnormal N-glycan profiles from 19 patients with known diagnoses of 11 different CDG subtypes were generated, some of which had previously been reported to have normal N-linked protein glycosylation by carbohydrate-deficient transferrin analysis. CONCLUSIONS The clinical specificity and sensitivity of N-glycan analysis was much improved with this method. Additional CDGs can be diagnosed that would be missed by carbohydrate-deficient transferrin analysis. The assay provides novel biomarkers with diagnostic and potentially therapeutic significance.
Collapse
Affiliation(s)
- Jie Chen
- Division of Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA
| | - Xueli Li
- Division of Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA
| | - Andrew Edmondson
- Division of Human Genetics, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA
| | - Gail Ditewig Meyers
- Division of Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA
| | - Kosuke Izumi
- Division of Human Genetics, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA
| | - Amanda M Ackermann
- Division of Endocrinology and Diabetes, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA
| | - Eva Morava
- Department of Clinical Genomics, Mayo Clinic, Rochester, MN
| | - Can Ficicioglu
- Division of Human Genetics, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA
| | - Michael J Bennett
- Division of Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA.,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Miao He
- Division of Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA; .,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| |
Collapse
|
41
|
Møller RS, Hammer TB, Rubboli G, Lemke JR, Johannesen KM. From next-generation sequencing to targeted treatment of non-acquired epilepsies. Expert Rev Mol Diagn 2019; 19:217-228. [DOI: 10.1080/14737159.2019.1573144] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Rikke S. Møller
- Department of Epilepsy Genetics and Precision Medicine, The Danish Epilepsy Centre, Dianalund, Denmark
- Institute for Regional Health Services, University of Southern Denmark, Odense, Denmark
| | - Trine B. Hammer
- Department of Epilepsy Genetics and Precision Medicine, The Danish Epilepsy Centre, Dianalund, Denmark
| | - Guido Rubboli
- Department of Epilepsy Genetics and Precision Medicine, The Danish Epilepsy Centre, Dianalund, Denmark
- Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Johannes R. Lemke
- Institute of Human Genetics, University of Leipzig Hospitals and Clinics, Leipzig, Germany
| | - Katrine M. Johannesen
- Department of Epilepsy Genetics and Precision Medicine, The Danish Epilepsy Centre, Dianalund, Denmark
- Institute for Regional Health Services, University of Southern Denmark, Odense, Denmark
| |
Collapse
|
42
|
Sim NS, Seo Y, Lim JS, Kim WK, Son H, Kim HD, Kim S, An HJ, Kang HC, Kim SH, Kim DS, Lee JH. Brain somatic mutations in SLC35A2 cause intractable epilepsy with aberrant N-glycosylation. Neurol Genet 2018; 4:e294. [PMID: 30584598 PMCID: PMC6283456 DOI: 10.1212/nxg.0000000000000294] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 10/03/2018] [Indexed: 01/16/2023]
Abstract
OBJECTIVE To identify whether somatic mutations in SLC35A2 alter N-glycan structures in human brain tissues and cause nonlesional focal epilepsy (NLFE) or mild malformation of cortical development (mMCD). METHODS Deep whole exome and targeted sequencing analyses were conducted for matched brain and blood tissues from patients with intractable NLFE and patients with mMCD who are negative for mutations in mTOR pathway genes. Furthermore, tissue glyco-capture and nanoLC/mass spectrometry analysis were performed to examine N-glycosylation in affected brain tissue. RESULTS Six of the 31 (19.3%) study patients exhibited brain-only mutations in SLC35A2 (mostly nonsense and splicing site mutations) encoding a uridine diphosphate (UDP)-galactose transporter. Glycome analysis revealed the presence of an aberrant N-glycan series, including high degrees of N-acetylglucosamine, in brain tissues with SLC35A2 mutations. CONCLUSION Our study suggests that brain somatic mutations in SLC35A2 cause intractable focal epilepsy with NLFE or mMCD via aberrant N-glycosylation in the affected brain.
Collapse
Affiliation(s)
- Nam Suk Sim
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Youngsuk Seo
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Jae Seok Lim
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Woo Kyeong Kim
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Hyeonju Son
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Heung Dong Kim
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Sangwoo Kim
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Hyun Joo An
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Hoon-Chul Kang
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Se Hoon Kim
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Dong-Seok Kim
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Jeong Ho Lee
- Graduate School of Medical Science and Engineering (N.S.S., J.S.L., W.K.K., J.H.L.), KAIST; Asia Glycomics Reference Site (Y.S., H.J.A.); Graduate School of Analytical Science & Technology (Y.S., H.J.A.), Chungnam National University, Daejeon, Korea; Department of Biomedical System informatics (H.S., S.K.), Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine; Division of Pediatric Neurology (H.D.K., H.C.K.), Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital; Epilepsy Research Institute (H.D.K., H.C.K.), Yonsei University College of Medicine; Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea; and Pediatric Neurosurgery (D.S.K.), Severance Children's Hospital, Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| |
Collapse
|
43
|
Yates TM, Suri M, Desurkar A, Lesca G, Wallgren-Pettersson C, Hammer TB, Raghavan A, Poulat AL, Møller RS, Thuresson AC, Balasubramanian M. SLC35A2-related congenital disorder of glycosylation: Defining the phenotype. Eur J Paediatr Neurol 2018; 22:1095-1102. [PMID: 30194038 DOI: 10.1016/j.ejpn.2018.08.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 08/10/2018] [Accepted: 08/19/2018] [Indexed: 12/01/2022]
Abstract
We aim to further delineate the phenotype associated with pathogenic variants in the SLC35A2 gene, and review all published literature to-date. This gene is located on the X chromosome and encodes a UDP-galactose transporter. Pathogenic variants in SLC35A2 cause a congenital disorder of glycosylation. The condition is rare, and less than twenty patients have been reported to-date. The phenotype is complex and has not been fully defined. Here, we present a series of five patients with de novo pathogenic variants in SLC35A2. The patients' phenotype includes developmental and epileptic encephalopathy with hypsarrhythmia, facial dysmorphism, severe intellectual disability, skeletal abnormalities, congenital cardiac disease and cortical visual impairment. Developmental and epileptic encephalopathy with hypsarrhythmia is present in most patients with SLC35A2 variants, and is drug-resistant in the majority of cases. Adrenocorticotropic hormone therapy may achieve partial or complete remission of seizures, but the effect is usually temporary. Isoelectric focusing of transferrins may be normal after infancy, therefore a congenital disorder of glycosylation should still be considered as a diagnosis in the presence of a suggestive phenotype. We also provide evidence that cortical visual impairment is part of the phenotypic spectrum.
Collapse
Affiliation(s)
- T Michael Yates
- Sheffield Clinical Genetics Service, Sheffield Children's NHS Foundation Trust, Sheffield, UK
| | - Mohnish Suri
- Nottingham Clinical Genetics Service, Nottingham University Hospitals NHS Trust, City Hospital Campus, Nottingham, UK
| | - Archana Desurkar
- Department of Paediatric Neurology, Sheffield Children's NHS Foundation Trust, Sheffield, UK
| | - Gaetan Lesca
- Hospices Civils de Lyon, Service de Génétique, CHU de Lyon, Lyon, France
| | - Carina Wallgren-Pettersson
- Department of Medical and Clinical Genetics, University of Helsinki and the Folkhaelsan Institute of Genetics, Helsinki, Finland
| | - Trine B Hammer
- The Danish Epilepsy Center Filadelfia, Dianalund, Denmark
| | - Ashok Raghavan
- Department of Radiology, Sheffield Children's NHS Foundation Trust, Sheffield, UK
| | - Anne-Lise Poulat
- Hospices Civils de Lyon, Service de Génétique, CHU de Lyon, Lyon, France
| | - Rikke S Møller
- The Danish Epilepsy Center Filadelfia, Dianalund, Denmark; Institute for Regional Health Research, University of Southern Denmark, Odense, Denmark
| | - Ann-Charlotte Thuresson
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory Uppsala, Uppsala University, Uppsala, Sweden
| | - Meena Balasubramanian
- Sheffield Clinical Genetics Service, Sheffield Children's NHS Foundation Trust, Sheffield, UK; Academic Unit of Child Health, Department of Oncology & Metabolism, University of Sheffield, UK.
| |
Collapse
|
44
|
Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2013-2014. MASS SPECTROMETRY REVIEWS 2018; 37:353-491. [PMID: 29687922 DOI: 10.1002/mas.21530] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 11/29/2016] [Indexed: 06/08/2023]
Abstract
This review is the eighth update of the original article published in 1999 on the application of Matrix-assisted laser desorption/ionization mass spectrometry (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2014. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation, and arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly- saccharides, glycoproteins, glycolipids, glycosides, and biopharmaceuticals. Much of this material is presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions, and applications to chemical synthesis. © 2018 Wiley Periodicals, Inc. Mass Spec Rev 37:353-491, 2018.
Collapse
Affiliation(s)
- David J Harvey
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7FZ, United Kingdom
| |
Collapse
|
45
|
Westenfield K, Sarafoglou K, Speltz LC, Pierpont EI, Steyermark J, Nascene D, Bower M, Pierpont ME. Mosaicism of the UDP-Galactose transporter SLC35A2 in a female causing a congenital disorder of glycosylation: a case report. BMC MEDICAL GENETICS 2018; 19:100. [PMID: 29907092 PMCID: PMC6003163 DOI: 10.1186/s12881-018-0617-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 05/24/2018] [Indexed: 01/10/2023]
Abstract
BACKGROUND Congenital disorders of glycosylation are rare conditions caused by genetic defects in glycan synthesis, processing or transport. Most congenital disorders of glycosylation involve defects in the formation or transfer of the lipid-linked oligosaccharide precursor of N-linked glycans. SLC35A2-CDG (previously CDG-IIm) is caused by hemizygous or heterozygous mutations in the X-linked gene SLC35A2 that encodes a UDP-galactose transporter. To date there have only been 10 reported patients with SLC35A2 mutations. Importantly, the patient presented here was not identified in infancy by transferrin isoform analysis, the most common testing to identify patients with a congenital disorder of glycosylation. CASE PRESENTATION A 27 month old girl with developmental delay, central hypotonia, cerebral atrophy, and failure to thrive with growth retardation was identified by whole exome sequencing to have a mosaic missense variant in SLC35A2 (c.991G > A). This particular variant has been previously reported in a male as a mutation. Comparison of all clinical findings and new information on growth pattern, growth hormone testing and neurodevelopmental evaluation are detailed on the patient presented. CONCLUSION This patient report increases the clinical and scientific knowledge of SLC35A2-CDG, a rare condition. New information on reduced growth, growth hormone sufficiency, lack of seizures, and neurodevelopmental status are presented. This new information will be helpful to clinicians caring for individuals with SLC35A2-CDG. This report also alerts clinicians that transferrin isoform measurements do not identify all patients with congenital disorders of glycosylation.
Collapse
Affiliation(s)
- Kristen Westenfield
- Department of Pediatrics, University of Minnesota, 2450 Riverside Avenue, Minneapolis, MN, 55454, USA
| | - Kyriakie Sarafoglou
- Divisions of Endocrinology, Genetics & Metabolism, University of Minnesota, 2450 Riverside Avenue, Minneapolis, MN, 55454, USA
| | - Laura C Speltz
- Department of Neurology, Gillette Children's Hospital, 200 University Avenue East, St. Paul, MN, 55101, USA
| | - Elizabeth I Pierpont
- Division of Clinical Behavioral Neuroscience, Department of Pediatrics, University of Minnesota, 420 Delaware Street SE, Minneapolis, MN, 55455-0392, USA
| | - Joan Steyermark
- University of Minnesota Masonic Children's Hospital, 2450 Riverside Avenue, Minneapolis, MN, 55454, USA
| | - David Nascene
- Department of Radiology, University of Minnesota, 420 Delaware St. SE, Minneapolis, MN, 55455, USA
| | - Matthew Bower
- Molecular Diagnostics Laboratory, University of Minnesota Medical Center, 420 Delaware St SE, Minneapolis, MN, 55455, USA
| | - Mary Ella Pierpont
- Division of Genetics & Metabolism, Department of Pediatrics and Ophthalmology, 2450 Riverside Avenue, Minneapolis, MN, 55454, USA.
| |
Collapse
|
46
|
Evaluating the pathogenic potential of genes with de novo variants in epileptic encephalopathies. Genet Med 2018; 21:17-27. [PMID: 29895856 PMCID: PMC6752304 DOI: 10.1038/s41436-018-0011-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 03/20/2018] [Indexed: 01/08/2023] Open
Abstract
Epileptic encephalopathies comprise a group of catastrophic epilepsies with heterogeneous genetic etiology. Although next-generation sequencing techniques can reveal a number of de novo variants in epileptic encephalopathies, evaluating the pathogenicity of these variants can be challenging. Determining the pathogenic potential of genes in epileptic encephalopathies is critical before evaluating the pathogenicity of variants identified in an individual. We reviewed de novo variants in epileptic encephalopathies, including their genotypes and functional consequences. We then evaluated the pathogenic potential of genes, with the following additional considerations: (1) recurrence of variants in unrelated cases, (2) information of previously defined phenotypes, and (3) data from genetic experimental studies. Genes related to epileptic encephalopathy revealed pathogenicity with distinct functional alterations, i.e., either a gain of function or loss of function in the majority; however, several genes warranted further study to confirm their pathogenic potential. Whether a gene was associated with distinct phenotype, the genotype (or functional alteration)-–phenotype correlation, and quantitative correlation between genetic impairment and phenotype severity were suggested to be specific evidence in determining the pathogenic role of genes. Data from epileptic encephalopathy-related genes would be helpful in outlining guidelines for evaluating the pathogenic potential of genes in other genetic disorders.
Collapse
|
47
|
Abstract
Neonatal epilepsy genetics is a rapidly expanding field with recent technological advances in genomics leading to an expanding list of genetic disorders associated with neonatal-onset epilepsy. The genetic causes of neonatal epilepsy can be grouped into the following categories: (i) malformations of cortical development, (ii) genetic-metabolic, (iii) genetic-vascular, (iv) genetic-syndromic, and (v) genetic-cellular. Clinically, epilepsy in the neonate shows phenotypic overlap with pathogenic variants in unrelated genes causing similar clinical presentation (locus heterogeneity) and variants in the same gene leading to a wide clinical spectrum ranging from benign familial neonatal seizures to more severe epileptic encephalopathies (variable expressivity). We suggest a diagnostic approach to obtaining a genetic diagnosis with emphasis on clinical features such as electro-clinical phenotype and magnetic resonance imaging findings. Rapid identification of genetic disorders with targeted treatments should be a clinical priority. Achieving a genetic diagnosis can be challenging in a rapidly changing genetic landscape, but is increasingly possible.
Collapse
|
48
|
Winawer MR, Griffin NG, Samanamud J, Baugh EH, Rathakrishnan D, Ramalingam S, Zagzag D, Schevon CA, Dugan P, Hegde M, Sheth SA, McKhann GM, Doyle WK, Grant GA, Porter BE, Mikati MA, Muh CR, Malone CD, Bergin AMR, Peters JM, McBrian DK, Pack AM, Akman CI, LaCoursiere CM, Keever KM, Madsen JR, Yang E, Lidov HG, Shain C, Allen AS, Canoll P, Crino PB, Poduri AH, Heinzen EL. Somatic SLC35A2 variants in the brain are associated with intractable neocortical epilepsy. Ann Neurol 2018; 83:1133-1146. [PMID: 29679388 PMCID: PMC6105543 DOI: 10.1002/ana.25243] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 04/01/2018] [Accepted: 04/18/2018] [Indexed: 12/27/2022]
Abstract
OBJECTIVE Somatic variants are a recognized cause of epilepsy-associated focal malformations of cortical development (MCD). We hypothesized that somatic variants may underlie a wider range of focal epilepsy, including nonlesional focal epilepsy (NLFE). Through genetic analysis of brain tissue, we evaluated the role of somatic variation in focal epilepsy with and without MCD. METHODS We identified somatic variants through high-depth exome and ultra-high-depth candidate gene sequencing of DNA from epilepsy surgery specimens and leukocytes from 18 individuals with NLFE and 38 with focal MCD. RESULTS We observed somatic variants in 5 cases in SLC35A2, a gene associated with glycosylation defects and rare X-linked epileptic encephalopathies. Nonsynonymous variants in SLC35A2 were detected in resected brain, and absent from leukocytes, in 3 of 18 individuals (17%) with NLFE, 1 female and 2 males, with variant allele frequencies (VAFs) in brain-derived DNA of 2 to 14%. Pathologic evaluation revealed focal cortical dysplasia type Ia (FCD1a) in 2 of the 3 NLFE cases. In the MCD cohort, nonsynonymous variants in SCL35A2 were detected in the brains of 2 males with intractable epilepsy, developmental delay, and magnetic resonance imaging suggesting FCD, with VAFs of 19 to 53%; Evidence for FCD was not observed in either brain tissue specimen. INTERPRETATION We report somatic variants in SLC35A2 as an explanation for a substantial fraction of NLFE, a largely unexplained condition, as well as focal MCD, previously shown to result from somatic mutation but until now only in PI3K-AKT-mTOR pathway genes. Collectively, our findings suggest a larger role than previously recognized for glycosylation defects in the intractable epilepsies. Ann Neurol 2018.
Collapse
Affiliation(s)
- Melodie R. Winawer
- Gertrude H. Sergievsky Center, Columbia University, New York, NY 10032, USA
- Department of Neurology, Columbia University, New York, NY 10032, USA
| | - Nicole G. Griffin
- Institute for Genomic Medicine, Columbia University, New York, NY, 10032, USA
| | - Jorge Samanamud
- Department of Neurosurgery, Columbia University, New York Presbyterian Hospital, New York, NY, 10032, USA
| | - Evan H. Baugh
- Institute for Genomic Medicine, Columbia University, New York, NY, 10032, USA
| | | | | | - David Zagzag
- Department of Pathology, New York University Langone Medical Center, New York, NY, 10016, USA
- Department of Neurosurgery, New York University Langone Medical Center, New York, NY, 10016, USA
| | | | - Patricia Dugan
- Department of Neurology, New York University Langone Medical Center, New York, NY, 10016, USA
| | - Manu Hegde
- Department of Neurology, University of California, San Francisco, San Francisco, CA 94143 USA
| | - Sameer A. Sheth
- Department of Neurological Surgery, Columbia University, New York, NY, 10032, USA
| | - Guy M. McKhann
- Department of Neurological Surgery, Columbia University, New York, NY, 10032, USA
| | - Werner K. Doyle
- Department of Neurosurgery, New York University Langone Medical Center, New York, NY, 10016, USA
| | - Gerald A. Grant
- Department of Neurosurgery, Lucile Packard Children’s Hospital at Stanford, Stanford, CA, 94305, USA
| | - Brenda E. Porter
- Department of Neurology, Lucile Packard Children’s Hospital at Stanford, Stanford, CA 94305
| | - Mohamad A. Mikati
- Division of Pediatric Neurology, Duke University Medical Center, Durham, NC, 27710, USA
- Department of Neurobiology, Duke University, Durham, NC, 27708, USA
| | - Carrie R. Muh
- Department of Neurosurgery, Duke University Medical Center, Durham, NC, 27708, USA
| | - Colin D. Malone
- Institute for Genomic Medicine, Columbia University, New York, NY, 10032, USA
| | - Ann Marie R. Bergin
- Department of Neurology, Harvard Medical School, Boston, MA, 02115, USA
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children’s Hospital, Boston, MA, 02115, USA
| | - Jurriaan M. Peters
- Department of Neurology, Harvard Medical School, Boston, MA, 02115, USA
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children’s Hospital, Boston, MA, 02115, USA
| | - Danielle K. McBrian
- Division of Pediatric Neurology, Columbia University, New York, NY, 10032, USA
| | - Alison M. Pack
- Department of Neurology, Columbia University, New York, NY 10032, USA
| | - Cigdem I. Akman
- Division of Pediatric Neurology, Columbia University, New York, NY, 10032, USA
| | | | - Katherine M. Keever
- Department of Neurology, Translational Neuroscience Center, Boston Children’s Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Joseph R. Madsen
- Department of Neurosurgery, Boston Children’s Hospital and Department of Neurosurgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Edward Yang
- Department of Radiology, Boston Children’s Hospital and Department of Radiology, Harvard Medical School, Boston, MA, 02115, USA
| | - Hart G.W. Lidov
- Department of Pathology, Boston Children’s Hospital and Department of Pathology, Harvard Medical School, Boston, MA, 02115, USA
| | - Catherine Shain
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, 02115, USA
| | - Andrew S. Allen
- Department of Biostatistics and Bioinformatics, Duke University, Durham, NC, 27710, USA
| | - Peter Canoll
- Department of Pathology and Cell Biology, Columbia University, New York, NY, 10032, USA
| | - Peter B. Crino
- Department of Neurology, University of Maryland, School of Medicine, Baltimore, MD, 21201, USA
| | - Annapurna H. Poduri
- Department of Neurology, Harvard Medical School, Boston, MA, 02115, USA
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children’s Hospital, Boston, MA, 02115, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, 02115, USA
- F.M.Kirby Neurobiology Center, Boston Children’s Hospital, Boston, MA, 02115, USA
| | - Erin L. Heinzen
- Institute for Genomic Medicine, Columbia University, New York, NY, 10032, USA
- Department of Pathology and Cell Biology, Columbia University, New York, NY, 10032, USA
| |
Collapse
|
49
|
Hesse AN, Bevilacqua J, Shankar K, Reddi HV. Retrospective genotype-phenotype analysis in a 305 patient cohort referred for testing of a targeted epilepsy panel. Epilepsy Res 2018; 144:53-61. [PMID: 29778030 DOI: 10.1016/j.eplepsyres.2018.05.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 05/09/2018] [Accepted: 05/12/2018] [Indexed: 11/16/2022]
Abstract
PURPOSE Epilepsy is a diverse neurological condition with extreme genetic and phenotypic heterogeneity. The introduction of next-generation sequencing into the clinical laboratory has made it possible to investigate hundreds of associated genes simultaneously for a patient, even in the absence of a clearly defined syndrome. This has resulted in the detection of rare and novel mutations at a rate well beyond our ability to characterize their effects. This retrospective study reviews genotype data in the context of available phenotypic information on 305 patients spanning the epileptic spectrum to identify established and novel patterns of correlation. METHODS Our epilepsy panel comprising 377 genes was used to sequence 305 patients referred for genetic testing. Qualifying variants were annotated with phenotypic data obtained from either the test requisition form or supporting clinical documentation. Observed phenotypes were compared with established phenotypes in OMIM, published literature and the ILAEs 2010 report on genetic testing to assess congruity with known gene aberrations. RESULTS We identified a number of novel and recognized genetic variants consistent with established epileptic phenotypes. Forty-one pathogenic or predicted deleterious variants were detected in 39 patients with accompanying clinical documentation. Twenty-five of these variants across 15 genes were novel. Furthermore, evaluation of phenotype data for 194 patients with variants of unknown significance in genes with autosomal dominant and X-linked disease inheritance elucidated potentially disease-causing variants that were not currently characterized in the literature. CONCLUSIONS Assessment of key genotype-phenotype correlations from our cohort provide insight into variant classification, as well as the importance of including ILAE recommended genes as part of minimum panel content for comprehensive epilepsy tests. Many of the reported VUSs are likely genuine pathogenic variants driving the observed phenotypes, but not enough evidence is available for assertive classifications. Similar studies will provide more utility via mounting independent genotype-phenotype data from unrelated patients. The possible outcome would be a better molecular diagnostic product, with fewer indeterminate reports containing only VUSs.
Collapse
Affiliation(s)
- Andrew N Hesse
- Transgenomic Inc, 5 Science Park, New Haven, CT, 06511, USA
| | | | - Kritika Shankar
- Transgenomic Inc, 5 Science Park, New Haven, CT, 06511, USA.
| | - Honey V Reddi
- Transgenomic Inc, 5 Science Park, New Haven, CT, 06511, USA.
| |
Collapse
|
50
|
Ng BG, Freeze HH. Perspectives on Glycosylation and Its Congenital Disorders. Trends Genet 2018; 34:466-476. [PMID: 29606283 DOI: 10.1016/j.tig.2018.03.002] [Citation(s) in RCA: 159] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 03/04/2018] [Accepted: 03/05/2018] [Indexed: 12/12/2022]
Abstract
Congenital disorders of glycosylation (CDG) are a rapidly expanding group of metabolic disorders that result from abnormal protein or lipid glycosylation. They are often difficult to clinically diagnose because they broadly affect many organs and functions and lack clinical uniformity. However, recent technological advances in next-generation sequencing have revealed a treasure trove of new genetic disorders, expanded the knowledge of known disorders, and showed a critical role in infectious diseases. More comprehensive genetic tools specifically tailored for mammalian cell-based models have revealed a critical role for glycosylation in pathogen-host interactions, while also identifying new CDG susceptibility genes. We highlight recent advancements that have resulted in a better understanding of human glycosylation disorders, perspectives for potential future therapies, and mysteries for which we continue to seek new insights and solutions.
Collapse
Affiliation(s)
- Bobby G Ng
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Hudson H Freeze
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA.
| |
Collapse
|