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Hu HT, Hsueh YP. KLHL17 differentially controls the expression of AMPA- and KA-type glutamate receptors to regulate dendritic spine enlargement. J Neurochem 2024; 168:2155-2169. [PMID: 38898681 DOI: 10.1111/jnc.16148] [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: 03/20/2024] [Revised: 05/24/2024] [Accepted: 05/30/2024] [Indexed: 06/21/2024]
Abstract
Kelch-like family member 17 (KLHL17), an actin-associated adaptor protein, is linked to neurological disorders, including infantile spasms and autism spectrum disorders. The key morphological feature of Klhl17-deficient neurons is impaired dendritic spine enlargement, resulting in the amplitude of calcium events being increased. Our previous studies have indicated an involvement of F-actin and the spine apparatus in KLHL17-mediated dendritic spine enlargement. Here, we show that KLHL17 further employs different mechanisms to control the expression of two types of glutamate receptors, that is, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) and kainate receptors (KARs), to regulate dendritic spine enlargement and calcium influx. We deployed proteomics to reveal that KLHL17 interacts with N-ethylmaleimide-sensitive fusion protein (NSF) in neurons, with this interaction of KLHL17 and NSF enhancing NSF protein levels. Consistent with the function of NSF in regulating the surface expression of AMPAR, Klhl17 deficiency limits the surface expression of AMPAR, but not its total protein levels. The NSF pathway also contributes to synaptic F-actin distribution and the dendritic spine enlargement mediated by KLHL17. KLHL17 is known to act as an adaptor mediating degradation of the KAR subunit GluK2 by the CUL3 ubiquitin ligase complex, and Klhl17 deficiency impairs activity-dependent degradation of GluK2. Herein, we further demonstrate that GluK2 is critical to the increased amplitude of calcium influx in Klhl17-deficient neurons. Moreover, GluK2 is also involved in KLHL17-regulated dendritic spine enlargement. Thus, our study reveals that KLHL17 controls AMPAR and KAR expression via at least two mechanisms, consequently regulating dendritic spine enlargement. The regulatory effects of KLHL17 on these two glutamate receptors likely contribute to neuronal features in patients suffering from certain neurological disorders.
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Affiliation(s)
- Hsiao-Tang Hu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Yi-Ping Hsueh
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
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2
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Dos Santos Henrique S, França MJ, Silva Junior RC, Santos MLSF, do Valle DA. Neurodevelopmental disorder associated with gene ARF3: A case report. Am J Med Genet A 2024; 194:e63658. [PMID: 38712921 DOI: 10.1002/ajmg.a.63658] [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: 02/07/2024] [Revised: 04/21/2024] [Accepted: 04/27/2024] [Indexed: 05/08/2024]
Abstract
We present a case study of a patient exhibiting acquired microcephaly along with global developmental delay and drug-resistant epilepsy. Brain magnetic resonance imaging revealed distinctive features, including a Z-shaped morphology of the brainstem, volumetric reduction of white matter, diffuse thinning of the corpus callosum, and partial fusion of the cerebellar hemispheres at their most cranial portion. Whole-exome sequencing uncovered a pathogenic variant in the ARF3 gene c.200A>T, p.(Asp67Val). The neurodevelopmental disorder associated with the ARF3 gene is exceptionally rare, with only two previously documented cases in the literature. This disorder is characterized by global developmental delay and brain malformations, particularly affecting the white matter, cerebellum, and brainstem. It can also manifest as acquired microcephaly and epilepsy. These phenotypic characteristics align with Golgipathies, underscoring the significance of considering this group of conditions in relevant clinical contexts. In cases where a Z-shaped morphology of the brainstem is observed, ARF3-associated disorder should be included in the list of differential diagnoses.
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Affiliation(s)
| | | | | | | | - Daniel Almeida do Valle
- Pediatric Neurology Department, Hospital Pequeno Príncipe, Curitiba, Paraná, Brazil
- Medicine Faculty, Positivo University, Curitiba, Paraná, Brazil
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3
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Cheng M, Bai L, Yang Y, Liu W, Niu X, Chen Y, Tan Q, Yang X, Wu Q, Zhao HQ, Zhang Y. Novel copy number variations and phenotypes of infantile epileptic spasms syndrome. Clin Genet 2024; 106:161-179. [PMID: 38544467 DOI: 10.1111/cge.14520] [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: 12/17/2023] [Revised: 03/07/2024] [Accepted: 03/08/2024] [Indexed: 07/02/2024]
Abstract
We summarize the copy number variations (CNVs) and phenotype spectrum of infantile epileptic spasms syndrome (IESS) in a Chinese cohort. The CNVs were identified by genomic copy number variation sequencing. The CNVs and clinical data were analyzed. 74 IESS children with CNVs were enrolled. 35 kinds of CNVs were identified. There were 11 deletions and 5 duplications not reported previously in IESS, including 2 CNVs not reported in epilepsy. 87.8% were de novo, 9.5% were inherited from mother and 2.7% from father. Mosaicism occurred in one patient with Xq21.31q25 duplication. 16.2% (12/74) were 1p36 deletion, and 20.3% (15/74) were 15q11-q13 duplication. The age of seizure onset ranged from 17 days to 24 months. Seizure types included epileptic spasms, focal seizures, tonic seizures, and myoclonic seizures. All patients displayed developmental delay. Additional features included craniofacial anomaly, microcephaly, congenital heart defects, and hemangioma. 29.7% of patients were seizure-free for more than 12 months, and 70.3% still had seizures after trying 2 or more anti-seizure medications. In conclusion, CNVs is a prominent etiology of IESS. 1p36 deletion and 15q duplication occurred most frequently. CNV detection should be performed in patients with IESS of unknown causes, especially in children with craniofacial anomalies and microcephaly.
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Affiliation(s)
- Miaomiao Cheng
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Ling Bai
- Research and Development Center, Beijing USCI Medical Laboratory Co., Ltd, Beijing, China
| | - Ying Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Wenwei Liu
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Xueyang Niu
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Yi Chen
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Quanzhen Tan
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Xiaoling Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Qixi Wu
- Research and Development Center, Beijing USCI Medical Laboratory Co., Ltd, Beijing, China
| | - Han-Qing Zhao
- Research and Development Center, Beijing USCI Medical Laboratory Co., Ltd, Beijing, China
| | - Yuehua Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
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4
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Betzler IR, Hempel M, Mütze U, Kölker S, Winkler E, Dikow N, Garbade SF, Schaaf CP, Brennenstuhl H. Comparative analysis of gene and disease selection in genomic newborn screening studies. J Inherit Metab Dis 2024. [PMID: 38757337 DOI: 10.1002/jimd.12750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/19/2024] [Accepted: 04/30/2024] [Indexed: 05/18/2024]
Abstract
Genomic newborn screening (gNBS) is on the horizon given the decreasing costs of sequencing and the advanced understanding of the impact of genetic variants on health and diseases. Key to ongoing gNBS pilot studies is the selection of target diseases and associated genes to be included. In this study, we present a comprehensive analysis of seven published gene-disease lists from gNBS studies, evaluating gene-disease count, composition, group proportions, and ClinGen curations of individual disorders. Despite shared selection criteria, we observe substantial variation in total gene count (median 480, range 237-889) and disease group composition. An intersection was identified for 53 genes, primarily inherited metabolic diseases (83%, 44/53). Each study investigated a subset of exclusive gene-disease pairs, and the total number of exclusive gene-disease pairs was positively correlated with the total number of genes included per study. While most pairs receive "Definitive" or "Strong" ClinGen classifications, some are labeled as "Refuted" (n = 5) or "Disputed" (n = 28), particularly in genetic cardiac diseases. Importantly, 17%-48% of genes lack ClinGen curation. This study underscores the current absence of consensus recommendations for selection criteria for target diseases for gNBS resulting in diversity in proposed gene-disease pairs, their coupling with gene variations and the use of ClinGen curation. Our findings provide crucial insights into the selection of target diseases and accompanying gene variations for future gNBS program, emphasizing the necessity for ongoing collaboration and discussion about criteria harmonization for panel selection to ensure the screening's objectivity, integrity, and broad acceptance.
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Affiliation(s)
- Isabel R Betzler
- Institute of Human Genetics, Heidelberg University and University Hospital Heidelberg, Heidelberg, Germany
| | - Maja Hempel
- Institute of Human Genetics, Heidelberg University and University Hospital Heidelberg, Heidelberg, Germany
| | - Ulrike Mütze
- Centre for Child and Adolescent Medicine, Division of Child Neurology and Metabolic Medicine, Heidelberg University and University Hospital Heidelberg, Heidelberg, Germany
| | - Stefan Kölker
- Centre for Child and Adolescent Medicine, Division of Child Neurology and Metabolic Medicine, Heidelberg University and University Hospital Heidelberg, Heidelberg, Germany
| | - Eva Winkler
- Section of Translational Medical Ethics, National Center for Tumour Diseases, Heidelberg University and University Hospital Heidelberg, Heidelberg, Germany
| | - Nicola Dikow
- Institute of Human Genetics, Heidelberg University and University Hospital Heidelberg, Heidelberg, Germany
| | - Sven F Garbade
- Centre for Child and Adolescent Medicine, Division of Child Neurology and Metabolic Medicine, Heidelberg University and University Hospital Heidelberg, Heidelberg, Germany
| | - Christian P Schaaf
- Institute of Human Genetics, Heidelberg University and University Hospital Heidelberg, Heidelberg, Germany
| | - Heiko Brennenstuhl
- Institute of Human Genetics, Heidelberg University and University Hospital Heidelberg, Heidelberg, Germany
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Hu HT, Lin YJ, Wang UTT, Lee SP, Liou YH, Chen BC, Hsueh YP. Autism-related KLHL17 and SYNPO act in concert to control activity-dependent dendritic spine enlargement and the spine apparatus. PLoS Biol 2023; 21:e3002274. [PMID: 37651441 PMCID: PMC10499226 DOI: 10.1371/journal.pbio.3002274] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 09/13/2023] [Accepted: 07/24/2023] [Indexed: 09/02/2023] Open
Abstract
Dendritic spines, the tiny and actin-rich protrusions emerging from dendrites, are the subcellular locations of excitatory synapses in the mammalian brain that control synaptic activity and plasticity. Dendritic spines contain a specialized form of endoplasmic reticulum (ER), i.e., the spine apparatus, required for local calcium signaling and that is involved in regulating dendritic spine enlargement and synaptic plasticity. Many autism-linked genes have been shown to play critical roles in synaptic formation and plasticity. Among them, KLHL17 is known to control dendritic spine enlargement during development. As a brain-specific disease-associated gene, KLHL17 is expected to play a critical role in the brain, but it has not yet been well characterized. In this study, we report that KLHL17 expression in mice is strongly regulated by neuronal activity and KLHL17 modulates the synaptic distribution of synaptopodin (SYNPO), a marker of the spine apparatus. Both KLHL17 and SYNPO are F-actin-binding proteins linked to autism. SYNPO is known to maintain the structure of the spine apparatus in mature spines and contributes to synaptic plasticity. Our super-resolution imaging using expansion microscopy demonstrates that SYNPO is indeed embedded into the ER network of dendritic spines and that KLHL17 is closely adjacent to the ER/SYNPO complex. Using mouse genetic models, we further show that Klhl17 haploinsufficiency and knockout result in fewer dendritic spines containing ER clusters and an alteration of calcium events at dendritic spines. Accordingly, activity-dependent dendritic spine enlargement and neuronal activation (reflected by extracellular signal-regulated kinase (ERK) phosphorylation and C-FOS expression) are impaired. In addition, we show that the effect of disrupting the KLHL17 and SYNPO association is similar to the results of Klhl17 haploinsufficiency and knockout, further strengthening the evidence that KLHL17 and SYNPO act together to regulate synaptic plasticity. In conclusion, our findings unravel a role for KLHL17 in controlling synaptic plasticity via its regulation of SYNPO and synaptic ER clustering and imply that impaired synaptic plasticity contributes to the etiology of KLHL17-related disorders.
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Affiliation(s)
- Hsiao-Tang Hu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Yung-Jui Lin
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Ueh-Ting Tim Wang
- Affiliated Senior High School of National Taiwan Normal University, Taipei, Taiwan
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
| | - Sue-Ping Lee
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Yae-Huei Liou
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Bi-Chang Chen
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
| | - Yi-Ping Hsueh
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
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Demarest S, Jeste S, Agarwal N, Arkilo D, Asgharnejad M, Hsiao S, Thibert R. Efficacy, safety, and tolerability of soticlestat as adjunctive therapy for the treatment of seizures in patients with Dup15q syndrome or CDKL5 deficiency disorder in an open-label signal-finding phase II study (ARCADE). Epilepsy Behav 2023; 142:109173. [PMID: 37011526 DOI: 10.1016/j.yebeh.2023.109173] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 03/06/2023] [Accepted: 03/08/2023] [Indexed: 04/05/2023]
Abstract
OBJECTIVE Chromosome 15q duplication (Dup15q) syndrome and cyclin‑dependent kinase-like 5 deficiency disorder (CDD) are rare neurodevelopmental disorders associated with epileptic encephalopathies, with a lack of specifically approved treatment options. ARCADE assessed the efficacy and safety of adjunctive soticlestat (TAK-935) for the treatment of seizures in patients with Dup15q syndrome or CDD (NCT03694275). METHODS ARCADE was a phase II, open-label, pilot study of soticlestat (≤300 mg/day twice daily, weight-adjusted) in pediatric and adult patients 2-55 years of age with Dup15q syndrome or CDD who experienced ≥3 motor seizures per month in the 3 months before screening and at baseline. The 20-week treatment period consisted of a dose-optimization period and a 12-week maintenance period. Efficacy endpoints included the change from baseline in motor seizure frequency during the maintenance period and the proportion of treatment responders. Safety endpoints included the incidence of treatment-emergent adverse effects (TEAEs). RESULTS The modified-intent-to-treat population included 20 participants who received ≥1 dose of soticlestat and had ≥1 efficacy assessment (Dup15q syndrome, n = 8; CDD, n = 12). Soticlestat administration during the maintenance period was associated with a median change from baseline in motor seizure frequency of +11.7% in the Dup15q syndrome group and -23.6% in the CDD group. Reductions in all seizure frequency of -23.4% and -30.5% were also observed during the maintenance period in the Dup15q syndrome group and the CDD group, respectively. Most TEAEs were of mild or moderate severity. Serious TEAEs were reported by three patients (15.0%); none were considered drug related. The most common TEAEs were constipation, rash, and seizure. No deaths were reported. CONCLUSIONS Adjunctive soticlestat treatment was associated with a decrease in motor seizure frequency from baseline in patients with CDD and a decrease in all seizure frequency in both patient groups. Soticlestat treatment was associated with an increase in motor seizure frequency in patients with Dup15q syndrome.
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Affiliation(s)
- Scott Demarest
- Department of Pediatrics and Neurology, University of Colorado School of Medicine, Children's Hospital Colorado, Aurora, Colorado, USA.
| | - Shafali Jeste
- Division of Neurology, Children's Hospital Los Angeles, Los Angeles, California, USA.
| | - Nitin Agarwal
- Division of Pediatric Epilepsy, Minnesota Epilepsy Group, P.A., and Children's Minnesota, St Paul, Minnesota, USA.
| | - Dimitrios Arkilo
- Takeda Pharmaceutical Company Limited, Cambridge, Massachusetts, USA.
| | | | - Samuel Hsiao
- Takeda Pharmaceutical Company Limited, Cambridge, Massachusetts, USA.
| | - Ronald Thibert
- Massachusetts General Hospital for Children, Massachusetts General Hospital, Boston, Massachusetts, USA.
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7
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Riikonen R. Biochemical mechanisms in pathogenesis of infantile epileptic spasm syndrome. Seizure 2023; 105:1-9. [PMID: 36634586 DOI: 10.1016/j.seizure.2023.01.004] [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: 09/22/2022] [Revised: 01/01/2023] [Accepted: 01/05/2023] [Indexed: 01/09/2023] Open
Abstract
The molecular mechanisms leading to infantile epileptic spasm syndrome (IESS) remain obscure. The only common factor seems to be that the spasms are restricted to a limited period of infancy, during a certain maturational state. Here the current literature regarding the biochemical mechanisms of brain maturation in IESS is reviewed, and various hypotheses of the pathophysiology are put together. They include: (1) imbalance of inhibitory (NGF, IGF-1, ACTH, GABA) and excitatory factors (glutamate, nitrites) which distinguishes the different etiological subgroups, (2) abnormality of the hypothalamic pituitary adrenal (HPA) axis linking insults and early life stress, (3) inflammation (4) yet poorly known genetic and epigenetic factors, and (5) glucocorticoid and vigabatrin action on brain development, pinpointing at molecular targets of the pathophysiology from another angle. An altered maturational process may explain why so many, seemingly independent etiological factors lead to the same clinical syndrome and frequently to developmental delay. Understanding these factors can provide ideas for novel therapies.
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Affiliation(s)
- Raili Riikonen
- Children's Hospital, University of Eastern Finland and Kuopio University Hospital, Kuopio, Finland.
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8
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Liu LY, Lu Q, Wang QH, Wang YY, Zhang B, Zou LP. Diagnostic yield of a multi-strategy genetic testing procedure in a nationwide cohort of 728 patients with infantile spasms in China. Seizure 2022; 103:51-57. [DOI: 10.1016/j.seizure.2022.10.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 10/10/2022] [Accepted: 10/12/2022] [Indexed: 11/27/2022] Open
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Two Genetic Mechanisms in Two Siblings with Intellectual Disability, Autism Spectrum Disorder, and Psychosis. J Pers Med 2022; 12:jpm12061013. [PMID: 35743796 PMCID: PMC9224546 DOI: 10.3390/jpm12061013] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/08/2022] [Accepted: 06/17/2022] [Indexed: 12/04/2022] Open
Abstract
Intellectual disability (ID) and autism spectrum disorder (ASD) are complex neurodevelopmental disorders with high heritability. To search for the genetic deficits in two siblings affected with ID and ASD in a family, we first performed a genome-wide copy number variation (CNV) analysis using chromosomal microarray analysis (CMA). We found a 3.7 Mb microdeletion at 22q13.3 in the younger sister. This de novo microdeletion resulted in the haploinsufficiency of SHANK3 and several nearby genes involved in neurodevelopment disorders. Hence, she was diagnosed with Phelan–McDermid syndrome (PMS, OMIM#606232). We further performed whole-genome sequencing (WGS) analysis in this family. We did not detect pathogenic mutations with significant impacts on the phenotypes of the elder brother. Instead, we identified several rare, likely pathogenic variants in seven genes implicated in neurodevelopmental disorders: KLHL17, TDO2, TRRAP, EIF3F, ATP10A, DICER1, and CDH15. These variants were transmitted from his unaffected parents, indicating these variants have only moderate clinical effects. We propose that these variants worked together and led to the clinical phenotypes in the elder brother. We also suggest that the combination of multiple genes with moderate effects is part of the genetic mechanism of neurodevelopmental disorders.
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10
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Demarest S, Calhoun J, Eschbach K, Yu HC, Mirsky D, Angione K, Shaikh TH, Carvill GL, Benke TA, Gunti J, Vanderveen G. Whole-exome sequencing and adrenocorticotropic hormone therapy in individuals with infantile spasms. Dev Med Child Neurol 2022; 64:633-640. [PMID: 35830182 DOI: 10.1111/dmcn.15109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 10/22/2021] [Accepted: 10/25/2021] [Indexed: 12/20/2022]
Abstract
AIM To identify additional genes associated with infantile spasms using a cohort with defined infantile spasms. METHOD Whole-exome sequencing (WES) was performed on 21 consented individuals with infantile spasms and their unaffected parents (a trio-based study). Clinical history and imaging were reviewed. Potentially deleterious exonic variants were identified and segregated. To refine potential candidates, variants were further prioritized on the basis of evidence for relevance to disease phenotype or known associations with infantile spasms, epilepsy, or neurological disease. RESULTS Likely pathogenic de novo variants were identified in NR2F1, GNB1, NEUROD2, GABRA2, and NDUFAF5. Suggestive dominant and recessive candidate variants were identified in PEMT, DYNC1I1, ASXL1, RALGAPB, and STRADA; further confirmation is required to support their relevance to disease etiology. INTERPRETATION This study supports the utility of WES in uncovering the genetic etiology in undiagnosed individuals with infantile spasms with an overall yield of five out of 21. High-priority candidates were identified in an additional five individuals. WES provides additional support for previously described disease-associated genes and expands their already broad mutational and phenotypic spectrum.
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Affiliation(s)
- Scott Demarest
- Children's Hospital Colorado, Aurora, CO, USA.,Department of Pediatrics, University of Colorado, School of Medicine, Aurora, CO, USA
| | - Jeff Calhoun
- Ken and Ruth Davee Department of Neurology, Northwestern University, School of Medicine, Chicago, IL, USA
| | - Krista Eschbach
- Children's Hospital Colorado, Aurora, CO, USA.,Department of Pediatrics, University of Colorado, School of Medicine, Aurora, CO, USA
| | - Hung-Chun Yu
- Department of Pediatrics, University of Colorado, School of Medicine, Aurora, CO, USA
| | - David Mirsky
- Children's Hospital Colorado, Aurora, CO, USA.,Department of Radiology, University of Colorado, School of Medicine, Aurora, CO, USA
| | - Katie Angione
- Children's Hospital Colorado, Aurora, CO, USA.,Department of Pediatrics, University of Colorado, School of Medicine, Aurora, CO, USA
| | - Tamim H Shaikh
- Department of Pediatrics, University of Colorado, School of Medicine, Aurora, CO, USA
| | - Gemma L Carvill
- Ken and Ruth Davee Department of Neurology, Northwestern University, School of Medicine, Chicago, IL, USA.,Department of Pharmacology, Northwestern University, School of Medicine, Chicago, IL, USA.,Department of Pediatrics, Northwestern University, School of Medicine, Chicago, IL, USA
| | - Tim A Benke
- Children's Hospital Colorado, Aurora, CO, USA.,Department of Pediatrics, University of Colorado, School of Medicine, Aurora, CO, USA.,Department of Pharmacology, University of Colorado, School of Medicine, Aurora, CO, USA.,Department of Neurology, University of Colorado, School of Medicine, Aurora, CO, USA.,Department of Otolaryngology, University of Colorado, School of Medicine, Aurora, CO, USA
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11
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Hu HT, Huang TN, Hsueh YP. KLHL17/Actinfilin, a brain-specific gene associated with infantile spasms and autism, regulates dendritic spine enlargement. J Biomed Sci 2020; 27:103. [PMID: 33256713 PMCID: PMC7708131 DOI: 10.1186/s12929-020-00696-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 11/23/2020] [Indexed: 11/10/2022] Open
Abstract
Background Dendritic spines, the actin-rich protrusions emerging from dendrites, are the subcellular locations of excitatory synapses in the mammalian brain. Many actin-regulating molecules modulate dendritic spine morphology. Since dendritic spines are neuron-specific structures, it is reasonable to speculate that neuron-specific or -predominant factors are involved in dendritic spine formation. KLHL17 (Kelch-like 17, also known as Actinfilin), an actin-binding protein, is predominantly expressed in brain. Human genetic study has indicated an association of KLHL17/Actinfilin with infantile spasms, a rare form of childhood epilepsy also resulting in autism and mental retardation, indicating that KLHL17/Actinfilin plays a role in neuronal function. However, it remains elusive if and how KLHL17/Actinfilin regulates neuronal development and brain function. Methods Fluorescent immunostaining and electrophysiological recording were performed to evaluate dendritic spine formation and activity in cultured hippocampal neurons. Knockdown and knockout of KLHL17/Actinfilin and expression of truncated fragments of KLHL17/Actinfilin were conducted to investigate the function of KLHL17/Actinfilin in neurons. Mouse behavioral assays were used to evaluate the role of KLHL17/Actinfilin in brain function. Results We found that KLHL17/Actinfilin tends to form circular puncta in dendritic spines and are surrounded by or adjacent to F-actin. Klhl17 deficiency impairs F-actin enrichment at dendritic spines. Knockdown and knockout of KLHL17/Actinfilin specifically impair dendritic spine enlargement, but not the density or length of dendritic spines. Both N-terminal Broad-Complex, Tramtrack and Bric-a-brac (BTB) domain and C-terminal Kelch domains of KLHL17/Actinfilin are required for F-actin remodeling and enrichment at dendritic spines, as well as dendritic spine enlargement. A reduction of postsynaptic and presynsptic markers at dendritic spines and altered mEPSC profiles due to Klhl17 deficiency evidence impaired synaptic activity in Klhl17-deficient neurons. Our behavioral assays further indicate that Klhl17 deficiency results in hyperactivity and reduced social interaction, strengthening evidence for the physiological role of KLHL17/Actinfilin. Conclusion Our findings provide evidence that KLHL17/Actinfilin modulates F-actin remodeling and contributes to regulation of neuronal morphogenesis, maturation and activity, which is likely relevant to behavioral impairment in Klhl17-deficient mice. Trial registration Non-applicable.
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Affiliation(s)
- Hsiao-Tang Hu
- Institute of Molecular Biology, Academia Sinica, 128, Academia Road, Section 2, Taipei, 11529, Taiwan, Republic of China
| | - Tzyy-Nan Huang
- Institute of Molecular Biology, Academia Sinica, 128, Academia Road, Section 2, Taipei, 11529, Taiwan, Republic of China
| | - Yi-Ping Hsueh
- Institute of Molecular Biology, Academia Sinica, 128, Academia Road, Section 2, Taipei, 11529, Taiwan, Republic of China.
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12
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Asmar AJ, Beck DB, Werner A. Control of craniofacial and brain development by Cullin3-RING ubiquitin ligases: Lessons from human disease genetics. Exp Cell Res 2020; 396:112300. [PMID: 32986984 PMCID: PMC10627151 DOI: 10.1016/j.yexcr.2020.112300] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/16/2020] [Accepted: 09/20/2020] [Indexed: 12/19/2022]
Abstract
Metazoan development relies on intricate cell differentiation, communication, and migration pathways, which ensure proper formation of specialized cell types, tissues, and organs. These pathways are crucially controlled by ubiquitylation, a reversible post-translational modification that regulates the stability, activity, localization, or interaction landscape of substrate proteins. Specificity of ubiquitylation is ensured by E3 ligases, which bind substrates and co-operate with E1 and E2 enzymes to mediate ubiquitin transfer. Cullin3-RING ligases (CRL3s) are a large class of multi-subunit E3s that have emerged as important regulators of cell differentiation and development. In particular, recent evidence from human disease genetics, animal models, and mechanistic studies have established their involvement in the control of craniofacial and brain development. Here, we summarize regulatory principles of CRL3 assembly, substrate recruitment, and ubiquitylation that allow this class of E3s to fulfill their manifold functions in development. We further review our current mechanistic understanding of how specific CRL3 complexes orchestrate neuroectodermal differentiation and highlight diseases associated with their dysregulation. Based on evidence from human disease genetics, we propose that other unknown CRL3 complexes must help coordinate craniofacial and brain development and discuss how combining emerging strategies from the field of disease gene discovery with biochemical and human pluripotent stem cell approaches will likely facilitate their identification.
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Affiliation(s)
- Anthony J Asmar
- Stem Cell Biochemistry Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
| | - David B Beck
- Stem Cell Biochemistry Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA; Metabolic, Cardiovascular and Inflammatory Disease Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Achim Werner
- Stem Cell Biochemistry Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA.
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Genotype-phenotype correlates of infantile-onset developmental & epileptic encephalopathy syndromes in South India: A single centre experience. Epilepsy Res 2020; 166:106398. [PMID: 32593896 DOI: 10.1016/j.eplepsyres.2020.106398] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 05/29/2020] [Accepted: 06/10/2020] [Indexed: 11/23/2022]
Abstract
INTRODUCTION A paucity of literature exists on genotype- phenotype correlates of 'unknown-etiology' infantile-onset developmental-epileptic encephalopathies (DEE) from India. The primary objective was to explore the yield of genetic testing in identifying potential disease causing variants in electro-clinical phenotypes of DEE METHODS: An observational hospital-based study was undertaken on children with unexplained refractory seizure-onset ≤12 months age and developmental delay, whose families consented and underwent genetic testing during a three year time period (2016-2018) by next-generation sequencing (NGS) or multiplex ligand protein amplification. Yield was considered based on demonstration of pathogenic/likely pathogenic variants only and variants of unknown significance (VUS) were documented. RESULTS Pathogenic/likely pathogenic variants were identified in 26 (31.7 %) out of 82 children with DEE. These included those variants responsible for primarily DEE- 21(76.7 %); neuro-metabolic disorders- 3(18.6 %) and chromosomal deletions- 2(4.7 %). Of these patients, early-infantile epilepsy onset ≤ 6 months age was noted in 22(84.6 %). The DEE studied included Ohtahara syndrome associated with STXBP1 and SCN8A variants with yield of 50 % (2/4 tested); early myoclonic encephalopathy (no yield in 2); West syndrome with CDKL5, yield of 13.3 % (2/15 tested); epilepsy of infancy with migrating partial seizures due to CACNA1A and KCNT1 variants, yield of 67 % (2/3 tested); DEE-unclassified with KCNQ2, AP3B2, ZEB2, metabolic variants (SUOX, ALDH7A1, GLDC) and chromosome deletions (chr 1p36, chr2q24.3); yield of 32 % (8/25 tested). Patients with Dravet syndrome/Dravet-like phenotypes (N = 33) had variants in SCN1A (N = 10), SCN1B, CHD2; yield of 36.4 % (12/33 tested; 57.1 % from NGS). Eighteen patients with potential variants (SCN1A, SCN2A, SCN8A, KCNQ2, ALDH7A1 which also included VUS) could be offered targeted therapy. CONCLUSIONS Our study confirms a good yield of genetic testing in neonatal and infantile-onset DEE provided robust phenotyping of infants is attempted with prognostic and therapeutic implications, particularly relevant to centres with resource constraints.
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FOXG1-Related Syndrome: From Clinical to Molecular Genetics and Pathogenic Mechanisms. Int J Mol Sci 2019; 20:ijms20174176. [PMID: 31454984 PMCID: PMC6747066 DOI: 10.3390/ijms20174176] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/23/2019] [Accepted: 08/25/2019] [Indexed: 12/29/2022] Open
Abstract
Individuals with mutations in forkhead box G1 (FOXG1) belong to a distinct clinical entity, termed “FOXG1-related encephalopathy”. There are two clinical phenotypes/syndromes identified in FOXG1-related encephalopathy, duplications and deletions/intragenic mutations. In children with deletions or intragenic mutations of FOXG1, the recognized clinical features include microcephaly, developmental delay, severe cognitive disabilities, early-onset dyskinesia and hyperkinetic movements, stereotypies, epilepsy, and cerebral malformation. In contrast, children with duplications of FOXG1 are typically normocephalic and have normal brain magnetic resonance imaging. They also have different clinical characteristics in terms of epilepsy, movement disorders, and neurodevelopment compared with children with deletions or intragenic mutations. FOXG1 is a transcriptional factor. It is expressed mainly in the telencephalon and plays a pleiotropic role in the development of the brain. It is a key player in development and territorial specification of the anterior brain. In addition, it maintains the expansion of the neural proliferating pool, and also regulates the pace of neocortical neuronogenic progression. It also facilitates cortical layer and corpus callosum formation. Furthermore, it promotes dendrite elongation and maintains neural plasticity, including dendritic arborization and spine densities in mature neurons. In this review, we summarize the clinical features, molecular genetics, and possible pathogenesis of FOXG1-related syndrome.
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Peycheva V, Kamenarova K, Ivanova N, Stamatov D, Avdjieva-Tzavella D, Alexandrova I, Zhelyazkova S, Pacheva I, Dimova P, Ivanov I, Litvinenko I, Bozhinova V, Tournev I, Simeonov E, Mitev V, Jordanova A, Kaneva R. Chromosomal microarray analysis of Bulgarian patients with epilepsy and intellectual disability. Gene 2018; 667:45-55. [DOI: 10.1016/j.gene.2018.05.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 04/13/2018] [Accepted: 05/03/2018] [Indexed: 12/08/2022]
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Abstract
Epilepsy is a chronic neurological disorder affecting 65 million people worldwide. The etiologies of seizures can often be identified as genetic, metabolic, structural, immunologic or infectious, but in many cases the cause is unknown with the current diagnostic tools. Epileptogenesis is a process during which genetic or other acquired etiologies/insults lead to functional, structural, or network reorganization changes in the brain that may lead to the development of, or progression of, spontaneous seizures. During development, there are continuous changes in the structure, function, and network operation that also show sex specificity, which may alter the mechanisms underlying the generation of seizures (ictogenesis) and epileptogenesis. Understanding the mechanisms of early life epileptogenesis will enable the development of rationally designed age- and sex-appropriate therapies that would improve the overall quality of patients' lives. Here, we discuss some of these processes that may affect seizure generation and epileptogenesis in the neonatal brain.
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Affiliation(s)
- Anna-Maria Katsarou
- Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, New York, USA,Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Aristea S. Galanopoulou
- Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, New York, USA,Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Bronx, New York, USA,Montefiore/Einstein Epilepsy Center, Albert Einstein College of Medicine, Bronx, New York, USA,Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Solomon L. Moshé
- Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, New York, USA,Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Bronx, New York, USA,Montefiore/Einstein Epilepsy Center, Albert Einstein College of Medicine, Bronx, New York, USA,Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, USA,Department of Pediatrics, Albert Einstein College of Medicine, Bronx, New York, USA,Corresponding author. Address: Department of Neurology, Albert Einstein College of Medicine, 1410 Pelham Parkway South, Rose F. Kennedy Center, Rm 316, Bronx, NY 10461, USA. Tel.: +1 718-430-2447; fax: +1 718-430-8899. (S.L. Moshé)
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17
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Addis L, Sproviero W, Thomas SV, Caraballo RH, Newhouse SJ, Gomez K, Hughes E, Kinali M, McCormick D, Hannan S, Cossu S, Taylor J, Akman CI, Wolf SM, Mandelbaum DE, Gupta R, van der Spek RA, Pruna D, Pal DK. Identification of new risk factors for rolandic epilepsy: CNV at Xp22.31 and alterations at cholinergic synapses. J Med Genet 2018; 55:607-616. [PMID: 29789371 PMCID: PMC6119347 DOI: 10.1136/jmedgenet-2018-105319] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 04/18/2018] [Accepted: 04/28/2018] [Indexed: 12/25/2022]
Abstract
Background Rolandic epilepsy (RE) is the most common genetic childhood epilepsy, consisting of focal, nocturnal seizures and frequent neurodevelopmental impairments in speech, language, literacy and attention. A complex genetic aetiology is presumed in most, with monogenic mutations in GRIN2A accounting for >5% of cases. Objective To identify rare, causal CNV in patients with RE. Methods We used high-density SNP arrays to analyse the presence of rare CNVs in 186 patients with RE from the UK, the USA, Sardinia, Argentina and Kerala, India. Results We identified 84 patients with one or more rare CNVs, and, within this group, 14 (7.5%) with recurrent risk factor CNVs and 15 (8.0%) with likely pathogenic CNVs. Nine patients carried recurrent hotspot CNVs including at 16p13.11 and 1p36, with the most striking finding that four individuals (three from Sardinia) carried a duplication, and one a deletion, at Xp22.31. Five patients with RE carried a rare CNV that disrupted genes associated with other epilepsies (KCTD7, ARHGEF15, CACNA2D1, GRIN2A and ARHGEF4), and 17 cases carried CNVs that disrupted genes associated with other neurological conditions or that are involved in neuronal signalling/development. Network analysis of disrupted genes with high brain expression identified significant enrichment in pathways of the cholinergic synapse, guanine-exchange factor activation and the mammalian target of rapamycin. Conclusion Our results provide a CNV profile of an ethnically diverse cohort of patients with RE, uncovering new areas of research focus, and emphasise the importance of studying non-western European populations in oligogenic disorders to uncover a full picture of risk variation.
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Affiliation(s)
- Laura Addis
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, UK.,Neuroscience Discovery Research, Eli Lilly and Company, Surrey, UK
| | - William Sproviero
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, UK
| | - Sanjeev V Thomas
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
| | - Roberto H Caraballo
- Department of Neurology, Hospital de Pediatría Prof. Dr. J.P. Garrahan, Combate de los Pozos 1881, Buenos Aires, Argentina
| | - Stephen J Newhouse
- Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,NIHR Biomedical Research Centre at South London and Maudsley NHS Foundation Trust, Bethlem Royal Hospital, Beckenham, UK.,Farr Institute of Health Informatics Research, UCL Institute of Health Informatics, University College London, London, UK
| | - Kumudini Gomez
- Department of Paediatrics, University Hospital Lewisham, Lewisham and Greenwich NHS Trust, London, UK
| | - Elaine Hughes
- Department of Paediatric Neurosciences, Evelina London Children's Hospital, St Thomas' Hospital, London, UK
| | - Maria Kinali
- Department of Paediatric Neurology, Chelsea and Westminster Hospital, London, UK
| | - David McCormick
- Department of Paediatric Neurosciences, Evelina London Children's Hospital, St Thomas' Hospital, London, UK
| | - Siobhan Hannan
- Department of Paediatric Neurology, Chelsea and Westminster Hospital, London, UK
| | - Silvia Cossu
- Neurosurgery Unit, Neuroscience and Neurorehabilitation Department, Bambino Gesù Children Hospital, Rome, Italy.,Neurology Unit, Pediatric Hospital A. Cao, Brotzu Hospital Trust, Cagliari, Italy
| | | | - Cigdem I Akman
- Division of Pediatric Neurology, College of Physicians and Surgeons of Columbia University, New York City, New York, USA
| | - Steven M Wolf
- Department of Neurology, Mount Sinai Health System, New York City, New York, USA
| | - David E Mandelbaum
- Departments of Pediatrics, Alpert Medical School of Brown University, Providence, Rhode Island, USA
| | - Rajesh Gupta
- Department of Paediatrics, Tunbridge Wells Hospital, Pembury, UK
| | - Rick A van der Spek
- Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Dario Pruna
- Neurology Unit, Pediatric Hospital A. Cao, Brotzu Hospital Trust, Cagliari, Italy
| | - Deb K Pal
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, UK
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18
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Berg AT, Chakravorty S, Koh S, Grinspan ZM, Shellhaas RA, Saneto RP, Wirrell EC, Coryell J, Chu CJ, Mytinger JR, Gaillard WD, Valencia I, Knupp KG, Loddenkemper T, Sullivan JE, Poduri A, Millichap JJ, Keator C, Wusthoff C, Ryan N, Dobyns WB, Hegde M. Why West? Comparisons of clinical, genetic and molecular features of infants with and without spasms. PLoS One 2018. [PMID: 29518120 PMCID: PMC5843222 DOI: 10.1371/journal.pone.0193599] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Infantile spasms are the defining seizures of West syndrome, a severe form of early life epilepsy with poorly-understood pathophysiology. We present a novel comparative analysis of infants with spasms versus other seizure-types and identify clinical, etiological, and molecular-genetic factors preferentially predisposing to spasms. We compared ages, clinical etiologies, and associated-genes between spasms and non-spasms groups in a multicenter cohort of 509 infants (<12months) with newly-diagnosed epilepsy. Gene ontology and pathway enrichment analysis of clinical laboratory-confirmed pathogenic variant-harboring genes was performed. Pathways, functions, and cellular compartments between spasms and non-spasms groups were compared. Spasms onset age was similar in infants initially presenting with spasms (6.1 months) versus developing spasms as a later seizure type (6.9 months) but lower in the non-spasms group (4.7 months, p<0.0001). This pattern held across most etiological categories. Gestational age negatively correlated with spasms onset-age (r = -0.29, p<0.0001) but not with non-spasm seizure age. Spasms were significantly preferentially associated with broad developmental and regulatory pathways, whereas motor functions and pathways including cellular response to stimuli, cell motility and ion transport were preferentially enriched in non-spasms. Neuronal cell-body organelles preferentially associated with spasms, while, axonal, dendritic, and synaptic regions preferentially associated with other seizures. Spasms are a clinically and biologically distinct infantile seizure type. Comparative clinical-epidemiological analyses identify the middle of the first year as the time of peak expression regardless of etiology. The inverse association with gestational age suggests the preterm brain must reach a certain post-conceptional, not just chronological, neurodevelopmental stage before spasms manifest. Clear differences exist between the biological pathways leading to spasms versus other seizure types and suggest that spasms result from dysregulation of multiple developmental pathways and involve different cellular components than other seizure types. This deeper level of understanding may guide investigations into pathways most critical to target in future precision medicine efforts.
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Affiliation(s)
- Anne T. Berg
- Epilepsy Center, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, United States of America
- Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States of America
- * E-mail:
| | - Samya Chakravorty
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Sookyong Koh
- Department of Pediatrics, Children’s Healthcare of Atlanta, Emory University, Atlanta, GA, United States of America
| | - Zachary M. Grinspan
- Department of Healthcare Policy & Research, Weill Cornell Medicine, New York, NY, United States of America
- Department Pediatrics, Weill Cornell Medicine, New York, NY, United States of America
- New York Presbyterian Hospital, New York, NY, United States of America
| | - Renée A. Shellhaas
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States of America
| | - Russell P. Saneto
- Division of Pediatric Neurology, Seattle Children’s Hospital, Seattle, WA, United States of America
- Department of Neurology, University of Washington, Seattle, WA, United States of America
| | - Elaine C. Wirrell
- Department of Neurology, Mayo Clinic, Rochester, MN, United States of America
| | - Jason Coryell
- Departments of Pediatrics & Neurology, Oregon Health & Sciences University, Portland, OR, United States of America
| | - Catherine J. Chu
- Department of Neurology, Massachusetts General Hospital, Boston, MA, United States of America
| | - John R. Mytinger
- Department of Pediatrics, the Ohio State University, Nationwide Children’s Hospital, Columbus, OH, United States of America
| | - William D. Gaillard
- Department of Neurology, Children's National Health System, George Washington University School of Medicine, Washington, D.C., United States of America
| | - Ignacio Valencia
- Section of Neurology, St. Christopher's Hospital for Children, Drexel University College of Medicine, Philadelphia, PA, United States of America
| | - Kelly G. Knupp
- Department of Pediatrics and Neurology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States of America
| | - Tobias Loddenkemper
- Division of Epilepsy and Clinical Neurophysiology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, United States of America
| | - Joseph E. Sullivan
- Department of Neurology, University of California San Francisco, San Francisco, CA, United States of America
| | - Annapurna Poduri
- Division of Epilepsy and Clinical Neurophysiology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, United States of America
| | - John J. Millichap
- Epilepsy Center, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, United States of America
- Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States of America
| | - Cynthia Keator
- Cook Children’s Health Care System, Jane and John Justin Neurosciences Center, Fort Worth, TX, United States of America
| | - Courtney Wusthoff
- Division of Child Neurology, Stanford University, Palo Alto, CA, United States of America
| | - Nicole Ryan
- Departments of Neurology and Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA, United States of America
- The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States of America
| | - William B. Dobyns
- Division of Pediatric Neurology, Seattle Children’s Hospital, Seattle, WA, United States of America
- Department of Neurology, University of Washington, Seattle, WA, United States of America
- Center for Integrative Brain Research, University of Washington, Seattle, WA, United States of America
- Seattle Children's Research Institute, University of Washington, Seattle, WA, United States of America
- Pediatrics University of Washington, Seattle, WA, United States of America
| | - Madhuri Hegde
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, United States of America
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George AJ, Hoffiz YC, Charles AJ, Zhu Y, Mabb AM. A Comprehensive Atlas of E3 Ubiquitin Ligase Mutations in Neurological Disorders. Front Genet 2018; 9:29. [PMID: 29491882 PMCID: PMC5817383 DOI: 10.3389/fgene.2018.00029] [Citation(s) in RCA: 99] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 01/22/2018] [Indexed: 01/11/2023] Open
Abstract
Protein ubiquitination is a posttranslational modification that plays an integral part in mediating diverse cellular functions. The process of protein ubiquitination requires an enzymatic cascade that consists of a ubiquitin activating enzyme (E1), ubiquitin conjugating enzyme (E2) and an E3 ubiquitin ligase (E3). There are an estimated 600-700 E3 ligase genes representing ~5% of the human genome. Not surprisingly, mutations in E3 ligase genes have been observed in multiple neurological conditions. We constructed a comprehensive atlas of disrupted E3 ligase genes in common (CND) and rare neurological diseases (RND). Of the predicted and known human E3 ligase genes, we found ~13% were mutated in a neurological disorder with 83 total genes representing 70 different types of neurological diseases. Of the E3 ligase genes identified, 51 were associated with an RND. Here, we provide an updated list of neurological disorders associated with E3 ligase gene disruption. We further highlight research in these neurological disorders and discuss the advanced technologies used to support these findings.
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Affiliation(s)
- Arlene J. George
- Neuroscience Institute, Georgia State University, Atlanta, GA, United States
| | - Yarely C. Hoffiz
- Neuroscience Institute, Georgia State University, Atlanta, GA, United States
| | | | - Ying Zhu
- Creative Media Industries Institute & Department of Computer Science, Georgia State University, Atlanta, GA, United States
| | - Angela M. Mabb
- Neuroscience Institute, Georgia State University, Atlanta, GA, United States
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20
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Gao K, Zhang Y, Zhang L, Kong W, Xie H, Wang J, Wu Y, Wu X, Liu X, Zhang Y, Zhang F, Yu ACH, Jiang Y. Large De Novo Microdeletion in Epilepsy with Intellectual and Developmental Disabilities, with a Systems Biology Analysis. ADVANCES IN NEUROBIOLOGY 2018; 21:247-266. [DOI: 10.1007/978-3-319-94593-4_9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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21
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Greco M, Ferrara P, Farello G, Striano P, Verrotti A. Electroclinical features of epilepsy associated with 1p36 deletion syndrome: A review. Epilepsy Res 2017; 139:92-101. [PMID: 29212048 DOI: 10.1016/j.eplepsyres.2017.11.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 11/21/2017] [Accepted: 11/28/2017] [Indexed: 11/19/2022]
Abstract
1p36 terminal deletion is a recently recognized syndrome with multiple congenital anomalies and intellectual disability. It occurs approximately in 1 out of 5000 to 10,000 live births and is the most common subtelomeric microdeletion observed in human. Medical problems commonly caused by terminal deletions of 1p36 include developmental delay, intellectual disability, seizures, vision problems, hearing loss, short stature, brain anomalies, congenital heart defects, cardiomyopathy, renal anomalies and distinctive facial features. Although the syndrome is considered clinically recognizable, there is significant phenotypic variation among affected individuals. Genotype-phenotype correlation in this syndrome is complicated, because of the similar clinical evidence seen in patients with different deletion sizes. We review 34 scientific articles from 1996 to 2016 that described 315 patients with 1p36 delection syndrome. The aim of this review is to find a correlation between size of the 1p36-deleted segments and the neurological clinical phenotypes with the analysis of electro-clinical patterns associated with chromosomal aberrations, that is a major tool in the identification of epilepsy susceptibility genes. Our finding suggest that developmental delay and early epilepsy are frequent findings in 1p36 deletion syndrome that can contribute to a poor clinical outcome for this reason this syndrome should be searched for in patients presenting with infantile spasms associated with a hypsarrhythmic EEG, particulary if they are combined with dismorphic features, severe hypotonia and developmental delay.
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Affiliation(s)
- M Greco
- Department of Pediatrics, University of L'Aquila, L'Aquila, Italy.
| | - P Ferrara
- Institute of pediatrics, Catholic University of Sacred Hearth, Rome, Italy,.
| | - G Farello
- Department of Pediatrics, University of L'Aquila, L'Aquila, Italy,.
| | - P 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,.
| | - A Verrotti
- Department of Pediatrics, University of L'Aquila, L'Aquila, Italy,.
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22
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Davis PE, Filip-Dhima R, Sideridis G, Peters JM, Au KS, Northrup H, Bebin EM, Wu JY, Krueger D, Sahin M. Presentation and Diagnosis of Tuberous Sclerosis Complex in Infants. Pediatrics 2017; 140:e20164040. [PMID: 29101226 PMCID: PMC5703775 DOI: 10.1542/peds.2016-4040] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/25/2017] [Indexed: 01/07/2023] Open
Abstract
OBJECTIVES Tuberous sclerosis complex (TSC) is a neurocutaneous genetic disorder with a high prevalence of epilepsy and neurodevelopmental disorders. TSC can be challenging to diagnose in infants because they often do not show many clinical signs early in life. In this study, we describe the timing and pattern of presenting and diagnostic features in a prospective longitudinal study of infants with TSC. METHODS Two multicenter, prospective studies enrolled 130 infants with definite TSC by clinical or genetic criteria and followed them longitudinally up to 36 months of age. Periodic study visits included medical and seizure histories, physical and neurologic examinations, and developmental assessments. Ages at which major and minor features of TSC and seizures were first identified were analyzed. RESULTS The most common initial presenting features of TSC were cardiac rhabdomyomas (59%) and hypomelanotic macules or other skin findings (39%), and 85% of infants presented with either or both. Ultimately, the most prevalent diagnostic TSC features were hypomelanotic macules (94%), tubers or other cortical dysplasias (94%), subependymal nodules (90%), and cardiac rhabdomyomas (82%). Thirty-five percent of infants presented prenatally, 41% presented at birth or within the first month of life, and 74% met criteria for TSC diagnosis at or within 30 days of presentation. Seizure onset occurred before or at initial presentation in only 15% of infants, but 73% developed epilepsy within the first year of life. CONCLUSIONS Infants with TSC can often be identified early, before the onset of neurologic sequelae, enabling earlier diagnosis, surveillance, and possibly disease-modifying treatment.
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Affiliation(s)
| | - Rajna Filip-Dhima
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Harvard University, Boston, Massachusetts
| | | | - Jurriaan M Peters
- Departments of Neurology and
- Division of Epilepsy and Clinical Neurophysiology
| | - Kit Sing Au
- Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - Hope Northrup
- Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - E Martina Bebin
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Joyce Y Wu
- Division of Pediatric Neurology, University of California at Los Angeles Mattel Children's Hospital, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; and
| | - Darcy Krueger
- Department of Neurology and Rehabilitation Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Mustafa Sahin
- Departments of Neurology and
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Harvard University, Boston, Massachusetts
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Jackson MR, Lee K, Mattiske T, Jaehne EJ, Ozturk E, Baune BT, O'Brien TJ, Jones N, Shoubridge C. Extensive phenotyping of two ARX polyalanine expansion mutation mouse models that span clinical spectrum of intellectual disability and epilepsy. Neurobiol Dis 2017; 105:245-256. [DOI: 10.1016/j.nbd.2017.05.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 04/30/2017] [Accepted: 05/29/2017] [Indexed: 11/17/2022] Open
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Marquet V, Bourthoumieu S, Dobrescu A, Laroche-Raynaud C, Yardin C. Familial 1p36.3 microduplication resulting from a 1p-9q non-reciprocal translocation. Eur J Med Genet 2017; 60:583-588. [PMID: 28811188 DOI: 10.1016/j.ejmg.2017.08.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 06/22/2017] [Accepted: 08/10/2017] [Indexed: 10/19/2022]
Abstract
Unlike the 1p36 microdeletion syndrome, which has been extensively described, 1p36 microduplications have rarely been reported. We describe a three years old boy presenting with a severe global developmental delay and a few dysmorphic features. Cytogenetic analyses revealed a maternally inherited 3.35 Mb microduplication of chromosomal band 1p36.3. The maternal grandfather is also carrier of the same chromosomal rearrangement. Interestingly, the duplicated 1p36.3 segment was found to be localized at the telomeric end of the long arms of a chromosome 9, probably deriving from a 1p36.3-9qter non-reciprocal translocation. This particular type of chromosomal translocation has rarely been reported, and its mechanism is unclear. The phenotypical features associated with 1p36.3 microduplication vary due to the non-recurrent breakpoints of the rearrangements in this particular region. However when compiling the few described cases the phenotypical spectrum seems to include mainly developmental delay, mild facial dysmorphism, and neurological, cardiac and skeletal anomalies. The description of new patients carrying a 1p36.3 duplication like ours will lead to further delineation of the phenotypical spectrum and may help to find critical regions and causative genes implicated in the phenotype.
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Affiliation(s)
- Valentine Marquet
- Department of Cytology, Histology, Cytogenetics and Cellular Biology, Limoges University Hospital, France.
| | - Sylvie Bourthoumieu
- Department of Cytology, Histology, Cytogenetics and Cellular Biology, Limoges University Hospital, France
| | - Amelia Dobrescu
- Department of Cytology, Histology, Cytogenetics and Cellular Biology, Limoges University Hospital, France
| | | | - Catherine Yardin
- Department of Cytology, Histology, Cytogenetics and Cellular Biology, Limoges University Hospital, France; Limoges University, CNRS, XLIM, UMR 7252, F-87000 Limoges, France
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Jdila MB, Issa AB, Khabou B, Rhouma BB, Kamoun F, Ammar-Keskes L, Triki C, Fakhfakh F. Novel mutations in the CDKL5 gene in complex genotypes associated with West syndrome with variable phenotype: First description of somatic mosaic state. Clin Chim Acta 2017; 473:51-59. [PMID: 28780406 DOI: 10.1016/j.cca.2017.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Revised: 07/04/2017] [Accepted: 08/02/2017] [Indexed: 12/27/2022]
Abstract
INTRODUCTION West syndrome is a rare epileptic encephalopathy of early infancy, characterized by epileptic spasms, hypsarrhythmia, and psychomotor retardation beginning in the first year of life. METHODS The present study reports the clinical, molecular and bioinformatic investigation in the three studied West patients. RESULTS The results revealed a complex genotype with more than one mutation in each patient including the known mutations c.1910C>G (P2, P3); c.2372A>C in P3 and c.2395C>G in P1 and novel variants including c.616G>A, shared by the three patients P1, P2 and P3; c.1403G>C shared by P2 and P3 and c.2288A>G in patient P1. CONCLUSIONS All the mutations were at somatic mosaic state and were de novo in the patients except ones (c.2372A>C). To our knowledge; the somatic mosaic state is described for the first time in patients with West syndrome. Five identified mutations were located in the C-terminal domain of the protein, while the novel mutation (c.616G>A) was in the catalytic domain. Bioinformatic tools predicted that this latter is the most pathogenic substitution affecting 3D protein structure and the secondary mRNA structure. Complex genotype composed of different combinations of mutations in each patient seems to be related to the phenotype variability.
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Affiliation(s)
- Marwa Ben Jdila
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia; Laboratory of Human Molecular Genetics, Faculty of Medicine of Sfax, University of Sfax, Tunisia; Unité de recherche de Neuro-Pédiatrie (UR12ES 16) C.H.U. He'di Chaker de Sfax, Tunisia.
| | - Abir Ben Issa
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia; Laboratory of Human Molecular Genetics, Faculty of Medicine of Sfax, University of Sfax, Tunisia; Unité de recherche de Neuro-Pédiatrie (UR12ES 16) C.H.U. He'di Chaker de Sfax, Tunisia
| | - Boudour Khabou
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia; Laboratory of Human Molecular Genetics, Faculty of Medicine of Sfax, University of Sfax, Tunisia
| | - Bochra Ben Rhouma
- Laboratory of Human Molecular Genetics, Faculty of Medicine of Sfax, University of Sfax, Tunisia
| | - Fatma Kamoun
- Service de Neurologie Infantile, C.H.U. He'di Chaker de Sfax, Tunisia; Unité de recherche de Neuro-Pédiatrie (UR12ES 16) C.H.U. He'di Chaker de Sfax, Tunisia
| | - Leila Ammar-Keskes
- Laboratory of Human Molecular Genetics, Faculty of Medicine of Sfax, University of Sfax, Tunisia
| | - Chahnez Triki
- Service de Neurologie Infantile, C.H.U. He'di Chaker de Sfax, Tunisia; Unité de recherche de Neuro-Pédiatrie (UR12ES 16) C.H.U. He'di Chaker de Sfax, Tunisia
| | - Faiza Fakhfakh
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia.
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Fung CW, Kwong AKY, Wong VCN. Gene panel analysis for nonsyndromic cryptogenic neonatal/infantile epileptic encephalopathy. Epilepsia Open 2017; 2:236-243. [PMID: 29588952 PMCID: PMC5719849 DOI: 10.1002/epi4.12055] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/15/2017] [Indexed: 12/26/2022] Open
Abstract
Objective Epileptic encephalopathy (EE) is a heterogeneous condition associated with deteriorations of cognitive, sensory and/or motor functions as a consequence of epileptic activity. The phenomenon is the most common and severe in infancy and early childhood. Genetic-based diagnosis in EE patients is challenging owing to genetic and phenotypic heterogeneity of numerous monogenic disorders and the fact that thousands of genes are involved in neurodevelopment. Therefore, high-throughput next-generation sequencing (NGS) was used to investigate the genetic causes of non-syndromic cryptogenic neonatal/infantile EE (NIEE). Methods We have selected a cohort of 31 patients with seizure cryptogenic NIEE and seizure onset before 24 months. All investigations including metabolic work-up, were negative. Using NGS, we distinguished a panel of 430 epilepsy-associated genes by NGS was utilized to identify possible pathogenic variants in the patients. Segregation analysis and multiple silico analysis prediction tools were used for pathogenicity assessment. The identified variants were classified as "pathogenic," "likely pathogenic" and "uncertain significance," according to the American College of Medical Genetics (ACMG) guidelines. Results Pathogenic or likely pathogenic variants were identified in six genes (ALG13 [1], CDKL5 [2], KCNQ2 [2], PNPO [1], SCN8A [1], SLC9A6 [2]) in 9 NIEE patients (9/31; 29%). Variants of uncertain significance (VUS) were found in DNM1 and TUBA8 in 2 NIEE patients (2/31; 6%). Most phenotypes in our cohort matched with those reported cases. Significance The diagnostic rate (29%) of pathogenic and likely pathogenic variants was comparable to the recent studies of early-onset epileptic encephalopathy, indicating that gene panel analysis through NGS is a powerful tool to investigate cryptogenic NIEE in patients. Six percent of patients had neurometabolic disorders. Some of our diagnosed cases illustrated that successful molecular investigation may allow a better treatment strategy and avoid unnecessary and even invasive investigations. Functional analysis could be performed to further study the pathogenicity of the VUS identified in DNM1 and TUBA8.
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Affiliation(s)
- Cheuk-Wing Fung
- Division of Paediatric Neurology/Developmental Behavioural Paediatrics/Neurohabilitation Department of Paediatrics and Adolescent Medicine Li Ka Shing Faculty of Medicine the University of Hong Kong Hong Kong SAR China
| | - Anna Ka-Yee Kwong
- Division of Paediatric Neurology/Developmental Behavioural Paediatrics/Neurohabilitation Department of Paediatrics and Adolescent Medicine Li Ka Shing Faculty of Medicine the University of Hong Kong Hong Kong SAR China
| | - Virginia Chun-Nei Wong
- Division of Paediatric Neurology/Developmental Behavioural Paediatrics/Neurohabilitation Department of Paediatrics and Adolescent Medicine Li Ka Shing Faculty of Medicine the University of Hong Kong Hong Kong SAR China
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Shandra O, Moshé SL, Galanopoulou AS. Inflammation in Epileptic Encephalopathies. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2017; 108:59-84. [PMID: 28427564 DOI: 10.1016/bs.apcsb.2017.01.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
West syndrome (WS) is an infantile epileptic encephalopathy that manifests with infantile spasms (IS), hypsarrhythmia (in ~60% of infants), and poor neurodevelopmental outcomes. The etiologies of WS can be structural-metabolic pathologies (~60%), genetic (12%-15%), or of unknown origin. The current treatment options include hormonal treatment (adrenocorticotropic hormone and high-dose steroids) and the GABA aminotransferase inhibitor vigabatrin, while ketogenic diet can be given as add-on treatment in refractory IS. There is a need to identify new therapeutic targets and more effective treatments for WS. Theories about the role of inflammatory pathways in the pathogenesis and treatment of WS have emerged, being supported by both clinical and preclinical data from animal models of WS. Ongoing advances in genetics have revealed numerous genes involved in the pathogenesis of WS, including genes directly or indirectly involved in inflammation. Inflammatory pathways also interact with other signaling pathways implicated in WS, such as the neuroendocrine pathway. Furthermore, seizures may also activate proinflammatory pathways raising the possibility that inflammation can be a consequence of seizures and epileptogenic processes. With this targeted review, we plan to discuss the evidence pro and against the following key questions. Does activation of inflammatory pathways in the brain cause epilepsy in WS and does it contribute to the associated comorbidities and progression? Can activation of certain inflammatory pathways be a compensatory or protective event? Are there interactions between inflammation and the neuroendocrine system that contribute to the pathogenesis of WS? Does activation of brain inflammatory signaling pathways contribute to the transition of WS to Lennox-Gastaut syndrome? Are there any lead candidates or unexplored targets for future therapy development for WS targeting inflammation?
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Affiliation(s)
- Oleksii Shandra
- Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Solomon L Moshé
- Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Bronx, NY, United States; Montefiore/Einstein Epilepsy Center, Montefiore Medical Center, Bronx, NY, United States
| | - Aristea S Galanopoulou
- Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Bronx, NY, United States; Montefiore/Einstein Epilepsy Center, Montefiore Medical Center, Bronx, NY, United States.
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Larson A, Weisfeld-Adams JD, Benke TA, Bonnen PE. Cerebrotendinous Xanthomatosis Presenting with Infantile Spasms and Intellectual Disability. JIMD Rep 2016; 35:1-5. [PMID: 27858369 DOI: 10.1007/8904_2016_16] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 09/15/2016] [Accepted: 09/20/2016] [Indexed: 01/05/2023] Open
Abstract
Cerebrotendinous xanthomatosis (CTX) is an inborn error of metabolism leading to progressive multisystem disease. Symptoms often begin in the first decade of life with chronic diarrhea, cataracts, developmental delay, intellectual disability, and cerebellar or pyramidal dysfunction. Later manifestations include tendon xanthomas, polyneuropathy, and abnormal neuroimaging. Pathogenic biallelic variants in CYP27A1 leading to compromised function of sterol 27-hydroxylase result in accumulation of detectable toxic intermediates of bile acid synthesis rendering both genetic and biochemical testing effective diagnostic tools. Effective treatment with chenodeoxycholic acid is available, making early diagnosis critical for patient care. Here we report a new patient with CTX and describe the early signs of disease in this patient. Initial symptoms included infantile spasms, which have not previously been reported in CTX. Developmental delay, mild intellectual disability with measured cognitive decline in childhood, was also observed. These clinical signs do not traditionally compel testing for CTX, and we highlight the need to consider this rare but treatable disorder among the differential diagnosis of children with similar clinical presentation. Increased awareness of early signs of CTX is important for improving time to diagnosis for this patient population.
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Affiliation(s)
- Austin Larson
- Department of Pediatrics, Section of Genetics, University of Colorado School of Medicine, Aurora, CO, USA. .,Children's Hospital Colorado, Mail Stop 153, 13123 E 16th Ave, Aurora, CO, 80045, USA.
| | - James D Weisfeld-Adams
- Department of Pediatrics, Section of Genetics, University of Colorado School of Medicine, Aurora, CO, USA
| | - Tim A Benke
- Departments of Pediatrics, Pharmacology, Neurology and Otolaryngology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Penelope E Bonnen
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA.
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Ma M, Adams HR, Seltzer LE, Dobyns WB, Paciorkowski AR. Phenotype Differentiation of FOXG1 and MECP2 Disorders: A New Method for Characterization of Developmental Encephalopathies. J Pediatr 2016; 178:233-240.e10. [PMID: 27640358 PMCID: PMC5873956 DOI: 10.1016/j.jpeds.2016.08.032] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/14/2016] [Accepted: 08/09/2016] [Indexed: 01/07/2023]
Abstract
OBJECTIVE To differentiate developmental encephalopathies by creating a novel quantitative phenotyping tool. STUDY DESIGN We created the Developmental Encephalopathy Inventory (DEI) to differentiate disorders with complex multisystem neurodevelopmental symptoms. We then used the DEI to study the phenotype features of 20 subjects with FOXG1 disorder and 11 subjects with MECP2 disorder. RESULTS The DEI identified core domains of fine motor and expressive language that were severely impaired in both disorders. Individuals with FOXG1 disorder were overall more severely impaired. Subjects with FOXG1 disorder were less able to walk, had worse fine motor skills, more disability in receptive language and reciprocity, and had more disordered sleep than did subjects with MECP2 disorder (P <.05). Covariance, cluster, and principal component analysis confirmed a relationship between impaired awareness, reciprocity, and language in both disorders. In addition, abnormal ambulation was a first principal component for FOXG1 but not for MECP2 disorder, suggesting that impaired ambulation is a strong differentiating factor clinically between the 2 disorders. CONCLUSIONS We have developed a novel quantitative developmental assessment tool for developmental encephalopathies and propose this tool as a method to identify and illustrate core common and differential domains of disability in these complex disorders. These findings demonstrate clear phenotype differences between FOXG1 and MECP2 disorders.
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Affiliation(s)
- Mandy Ma
- University of Buffalo School of Medicine, Buffalo, NY
| | - Heather R. Adams
- Department of Neurology, University of Rochester Medical Center, Rochester, NY
| | - Laurie E. Seltzer
- Department of Neurology, University of Rochester Medical Center, Rochester, NY,Strong Epilepsy Center, University of Rochester Medical Center, Rochester, NY
| | - William B. Dobyns
- Department of Neurology, University of Washington, Seattle, WA,Division of Medical Genetics, Department of Pediatrics, University of Washington, Seattle, WA,Center for Integrative Brain Research, Seattle Children’s Research Institute, Seattle, WA
| | - Alex R. Paciorkowski
- Department of Neurology, University of Rochester Medical Center, Rochester, NY,Departments of Pediatrics and Biomedical Genetics, University of Rochester Medical Center, Rochester, NY,Center for Neural Development and Disease, University of Rochester Medical Center, Rochester, NY
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Battaglia A, Bernardini L, Torrente I, Novelli A, Scarselli G. Spectrum of epilepsy and electroencephalogram patterns in idic (15) syndrome. Am J Med Genet A 2016; 170:2531-9. [PMID: 27513709 DOI: 10.1002/ajmg.a.37844] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 06/29/2016] [Indexed: 12/22/2022]
Abstract
Previous reports summarized the seizure types occurring in patients with idic(15) syndrome. To better define this issue, we retrospectively analyzed the evolution of electroencephalogram findings and seizures in 35 patients with confirmed idic(15). Epilepsy occurred in 28 patients (80%), with a median age of onset of 3 years 3 months. The initial seizures were infantile spasms associated with a hypsarrhythmic electroencephalogram (nine patients), focal/generalized tonic (seven patients), or atypical absences (eight patients). High doses of oral steroids were given in all nine children with infantile spasms, with remission of seizures and resolution of electroencephalogram abnormalities. Among them, three were seizure free at the time of evaluation, but six later developed Lennox-Gastaut syndrome or Lennox-Gastaut-like syndrome. The eight patients with atypical absences developed Lennox-Gastaut syndrome or Lennox-Gastaut-like syndrome. Epilepsy was well controlled in 32% of the patients; satisfactorily controlled (seizures reduced >75%) in 21.4%; partially controlled (seizures reduced <50%) in 10.7%; and uncontrolled in 32%. One patient was not taking any anti-epileptic drugs by his parents' choice. Fourteen percent were on monotherapy; whereas the other 82% were on polytherapy. Seizures stopped at a median age of 5 years 5 months. The interictal electroencephalogram showed slow/sharp waves, and/or biphasic spikes-polyspikes, spike/wave complexes, and an excess of fast activity mainly over the fronto-temporal areas. Epilepsy is a major clinical challenge in patients with idic(15), associated with a poor prognosis in 55%. Frontal lobe seizures are a novel finding. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Agatino Battaglia
- Stella Maris Clinical Research Institute for Child and Adolescent Neurology and Psychiatry, Calambrone, Pisa, Italy.
| | - Laura Bernardini
- Mendel Laboratory IRCCS "Casa Sollievo della Sofferenza" Hospital, San Giovanni Rotondo, Rome, Italy
| | - Isabella Torrente
- Mendel Laboratory IRCCS "Casa Sollievo della Sofferenza" Hospital, San Giovanni Rotondo, Rome, Italy.,Department of Experimental Medicine, Sapienza University, Rome, Italy
| | | | - Gloria Scarselli
- Stella Maris Clinical Research Institute for Child and Adolescent Neurology and Psychiatry, Calambrone, Pisa, Italy
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Fregeau B, Kim B, Hernández-García A, Jordan V, Cho M, Schnur R, Monaghan K, Juusola J, Rosenfeld J, Bhoj E, Zackai E, Sacharow S, Barañano K, Bosch D, de Vries B, Lindstrom K, Schroeder A, James P, Kulch P, Lalani S, van Haelst M, van Gassen K, van Binsbergen E, Barkovich A, Scott D, Sherr E. De Novo Mutations of RERE Cause a Genetic Syndrome with Features that Overlap Those Associated with Proximal 1p36 Deletions. Am J Hum Genet 2016; 98:963-970. [PMID: 27087320 DOI: 10.1016/j.ajhg.2016.03.002] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 03/02/2016] [Indexed: 10/21/2022] Open
Abstract
Deletions of chromosome 1p36 affect approximately 1 in 5,000 newborns and are associated with developmental delay, intellectual disability, and defects involving the brain, eye, ear, heart, and kidney. Arginine-glutamic acid dipeptide repeats (RERE) is located in the proximal 1p36 critical region. RERE is a widely-expressed nuclear receptor coregulator that positively regulates retinoic acid signaling. Animal models suggest that RERE deficiency might contribute to many of the structural and developmental birth defects and medical problems seen in individuals with 1p36 deletion syndrome, although human evidence supporting this role has been lacking. In this report, we describe ten individuals with intellectual disability, developmental delay, and/or autism spectrum disorder who carry rare and putatively damaging changes in RERE. In all cases in which both parental DNA samples were available, these changes were found to be de novo. Associated features that were recurrently seen in these individuals included hypotonia, seizures, behavioral problems, structural CNS anomalies, ophthalmologic anomalies, congenital heart defects, and genitourinary abnormalities. The spectrum of defects documented in these individuals is similar to that of a cohort of 31 individuals with isolated 1p36 deletions that include RERE and are recapitulated in RERE-deficient zebrafish and mice. Taken together, our findings suggest that mutations in RERE cause a genetic syndrome and that haploinsufficiency of RERE might be sufficient to cause many of the phenotypes associated with proximal 1p36 deletions.
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Addis L, Rosch RE, Valentin A, Makoff A, Robinson R, Everett KV, Nashef L, Pal DK. Analysis of rare copy number variation in absence epilepsies. NEUROLOGY-GENETICS 2016; 2:e56. [PMID: 27123475 PMCID: PMC4830185 DOI: 10.1212/nxg.0000000000000056] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 01/04/2016] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To identify shared genes and pathways between common absence epilepsy (AE) subtypes (childhood absence epilepsy [CAE], juvenile absence epilepsy [JAE], and unclassified absence epilepsy [UAE]) that may indicate common mechanisms for absence seizure generation and potentially a diagnostic continuum. METHODS We used high-density single-nucleotide polymorphism arrays to analyze genome-wide rare copy number variation (CNV) in a cohort of 144 children with AEs (95 CAE, 26 UAE, and 23 JAE). RESULTS We identified CNVs that are known risk factors for AE in 4 patients, including 3x 15q11.2 deletion. We also expanded the phenotype at 4 regions more commonly identified in other neurodevelopmental disorders: 1p36.33 duplication, 1q21.1 deletion, 22q11.2 duplication, and Xp22.31 deletion and duplication. Fifteen patients (10.5%) were found to carry rare CNVs that disrupt genes associated with neuronal development and function (8 CAE, 2 JAE, and 5 UAE). Four categories of protein are each disrupted by several CNVs: (1) synaptic vesicle membrane or vesicle endocytosis, (2) synaptic cell adhesion, (3) synapse organization and motility via actin, and (4) gap junctions. CNVs within these categories are shared across the AE subtypes. CONCLUSIONS Our results have reinforced the complex and heterogeneous nature of the AEs and their potential for shared genetic mechanisms and have highlighted several pathways that may be important in epileptogenesis of absence seizures.
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Affiliation(s)
- Laura Addis
- Department of Basic and Clinical Neuroscience (L.A., R.E.R., A.V., A.M., D.K.P.), Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, United Kingdom; Neuroscience Discovery Research (L.A.), Eli Lilly and Company, Erl Wood, Surrey, United Kingdom; Wellcome Trust Centre for Neuroimaging (R.E.R.), Institute of Neurology, University College London, United Kingdom; Department of Clinical Neurophysiology (A.V.), Department of Neurology (L.N.), and Department of Child Health (D.K.P.), King's College Hospital, United Kingdom; Department of Paediatric Neurology (R.R.), Great Ormond Street Hospital, London, United Kingdom; and St George's University of London (K.V.E.), Cranmer Terrace, London, United Kingdom
| | - Richard E Rosch
- Department of Basic and Clinical Neuroscience (L.A., R.E.R., A.V., A.M., D.K.P.), Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, United Kingdom; Neuroscience Discovery Research (L.A.), Eli Lilly and Company, Erl Wood, Surrey, United Kingdom; Wellcome Trust Centre for Neuroimaging (R.E.R.), Institute of Neurology, University College London, United Kingdom; Department of Clinical Neurophysiology (A.V.), Department of Neurology (L.N.), and Department of Child Health (D.K.P.), King's College Hospital, United Kingdom; Department of Paediatric Neurology (R.R.), Great Ormond Street Hospital, London, United Kingdom; and St George's University of London (K.V.E.), Cranmer Terrace, London, United Kingdom
| | - Antonio Valentin
- Department of Basic and Clinical Neuroscience (L.A., R.E.R., A.V., A.M., D.K.P.), Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, United Kingdom; Neuroscience Discovery Research (L.A.), Eli Lilly and Company, Erl Wood, Surrey, United Kingdom; Wellcome Trust Centre for Neuroimaging (R.E.R.), Institute of Neurology, University College London, United Kingdom; Department of Clinical Neurophysiology (A.V.), Department of Neurology (L.N.), and Department of Child Health (D.K.P.), King's College Hospital, United Kingdom; Department of Paediatric Neurology (R.R.), Great Ormond Street Hospital, London, United Kingdom; and St George's University of London (K.V.E.), Cranmer Terrace, London, United Kingdom
| | - Andrew Makoff
- Department of Basic and Clinical Neuroscience (L.A., R.E.R., A.V., A.M., D.K.P.), Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, United Kingdom; Neuroscience Discovery Research (L.A.), Eli Lilly and Company, Erl Wood, Surrey, United Kingdom; Wellcome Trust Centre for Neuroimaging (R.E.R.), Institute of Neurology, University College London, United Kingdom; Department of Clinical Neurophysiology (A.V.), Department of Neurology (L.N.), and Department of Child Health (D.K.P.), King's College Hospital, United Kingdom; Department of Paediatric Neurology (R.R.), Great Ormond Street Hospital, London, United Kingdom; and St George's University of London (K.V.E.), Cranmer Terrace, London, United Kingdom
| | - Robert Robinson
- Department of Basic and Clinical Neuroscience (L.A., R.E.R., A.V., A.M., D.K.P.), Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, United Kingdom; Neuroscience Discovery Research (L.A.), Eli Lilly and Company, Erl Wood, Surrey, United Kingdom; Wellcome Trust Centre for Neuroimaging (R.E.R.), Institute of Neurology, University College London, United Kingdom; Department of Clinical Neurophysiology (A.V.), Department of Neurology (L.N.), and Department of Child Health (D.K.P.), King's College Hospital, United Kingdom; Department of Paediatric Neurology (R.R.), Great Ormond Street Hospital, London, United Kingdom; and St George's University of London (K.V.E.), Cranmer Terrace, London, United Kingdom
| | - Kate V Everett
- Department of Basic and Clinical Neuroscience (L.A., R.E.R., A.V., A.M., D.K.P.), Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, United Kingdom; Neuroscience Discovery Research (L.A.), Eli Lilly and Company, Erl Wood, Surrey, United Kingdom; Wellcome Trust Centre for Neuroimaging (R.E.R.), Institute of Neurology, University College London, United Kingdom; Department of Clinical Neurophysiology (A.V.), Department of Neurology (L.N.), and Department of Child Health (D.K.P.), King's College Hospital, United Kingdom; Department of Paediatric Neurology (R.R.), Great Ormond Street Hospital, London, United Kingdom; and St George's University of London (K.V.E.), Cranmer Terrace, London, United Kingdom
| | - Lina Nashef
- Department of Basic and Clinical Neuroscience (L.A., R.E.R., A.V., A.M., D.K.P.), Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, United Kingdom; Neuroscience Discovery Research (L.A.), Eli Lilly and Company, Erl Wood, Surrey, United Kingdom; Wellcome Trust Centre for Neuroimaging (R.E.R.), Institute of Neurology, University College London, United Kingdom; Department of Clinical Neurophysiology (A.V.), Department of Neurology (L.N.), and Department of Child Health (D.K.P.), King's College Hospital, United Kingdom; Department of Paediatric Neurology (R.R.), Great Ormond Street Hospital, London, United Kingdom; and St George's University of London (K.V.E.), Cranmer Terrace, London, United Kingdom
| | - Deb K Pal
- Department of Basic and Clinical Neuroscience (L.A., R.E.R., A.V., A.M., D.K.P.), Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, United Kingdom; Neuroscience Discovery Research (L.A.), Eli Lilly and Company, Erl Wood, Surrey, United Kingdom; Wellcome Trust Centre for Neuroimaging (R.E.R.), Institute of Neurology, University College London, United Kingdom; Department of Clinical Neurophysiology (A.V.), Department of Neurology (L.N.), and Department of Child Health (D.K.P.), King's College Hospital, United Kingdom; Department of Paediatric Neurology (R.R.), Great Ormond Street Hospital, London, United Kingdom; and St George's University of London (K.V.E.), Cranmer Terrace, London, United Kingdom
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McTague A, Howell KB, Cross JH, Kurian MA, Scheffer IE. The genetic landscape of the epileptic encephalopathies of infancy and childhood. Lancet Neurol 2016; 15:304-16. [DOI: 10.1016/s1474-4422(15)00250-1] [Citation(s) in RCA: 296] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 09/16/2015] [Accepted: 09/17/2015] [Indexed: 10/22/2022]
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Riikonen RS, Wallden T, Kokkonen H. Infantile spasms and 15q11.2q13.1 chromosome duplication in two successive generations. Eur J Paediatr Neurol 2016; 20:164-7. [PMID: 26685108 DOI: 10.1016/j.ejpn.2015.11.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 08/13/2015] [Accepted: 11/02/2015] [Indexed: 01/15/2023]
Abstract
Familial cases of West syndrome have been reported only in Japan. In that study no chromosomal analyses were made. It has been suggested that microarray analysis should be included in the diagnostic evaluation of patients with infantile spasms and developmental delay, when an evaluation for structural brain lesions and metabolic disorders reveal no abnormal findings. We report here the first case of infantile spasms and 15q11.2q13.1 chromosome duplication in two successive generations. The daughter and mother with infantile spasms, and the autistic son had the duplication. The clinical course of infantile spasms was very similar in the mother and daughter. The spasms were primarily considered to be of unknown aetiology. Chromosomal microarray analysis revealed a 6.2 Mb size 15q11.2q13.1 duplication. The duplication belongs to the 15q11q13 duplication syndrome (OMIM 608636) which when maternally derived is characterised by neuro-behavioural disorders like autism, hypotonia, cognitive deficit, language delay and epilepsy. The proportion of patients with unknown aetiology for infantile spasms will decrease when more careful chromosomal studies are made. Our report expands the phenotype of chromosome 15q duplication syndrome and is the first report of this abnormality in two successive generations of infantile spasms.
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Affiliation(s)
- Raili Sylvia Riikonen
- Children's Hospital and Science Service Center, University of Eastern Finland, Kuopio, Finland.
| | | | - Hannaleena Kokkonen
- Nothern Finland Laboratory Centre NordLab and Medical Research Centre, Oulu University Hospital and University of Oulu, Oulu, Finland.
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Galanopoulou AS, Moshé SL. Neonatal and Infantile Epilepsy: Acquired and Genetic Models. Cold Spring Harb Perspect Med 2015; 6:a022707. [PMID: 26637437 DOI: 10.1101/cshperspect.a022707] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The incidence of seizures and epilepsies is particularly high during the neonatal and infantile periods. We will review selected animal models of early-life epileptic encephalopathies that have addressed the dyscognitive features of frequent interictal spikes, the pathogenesis and treatments of infantile spasms (IS) or Dravet syndrome, disorders with mammalian target of rapamycin (mTOR) dysregulation, and selected early-life epilepsies with genetic defects. Potentially pathogenic mechanisms in these conditions include interneuronopathies in IS or Dravet syndrome and mTOR dysregulation in brain malformations, tuberous sclerosis, and related genetic disorders, or IS of acquired etiology. These models start to generate the first therapeutic drugs, which have been specifically developed in immature animals. However, there are challenges in translating preclinical discoveries into clinically relevant findings. The advances made so far hold promise that the new insights may potentially have curative or disease-modifying potential for many of these devastating conditions.
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Affiliation(s)
- Aristea S Galanopoulou
- Saul R. Korey Department of Neurology, Dominick P. Purpura Department of Neuroscience, Laboratory of Developmental Epilepsy, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Solomon L Moshé
- Saul R. Korey Department of Neurology, Dominick P. Purpura Department of Neuroscience, Laboratory of Developmental Epilepsy, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York 10461 Department of Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York 10461
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McMahon KQ, Papandreou A, Ma M, Barry BJ, Mirzaa GM, Dobyns WB, Scott RH, Trump N, Kurian MA, Paciorkowski AR. Familial recurrences of FOXG1-related disorder: Evidence for mosaicism. Am J Med Genet A 2015; 167A:3096-102. [PMID: 26364767 DOI: 10.1002/ajmg.a.37353] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 08/13/2015] [Indexed: 12/18/2022]
Abstract
FOXG1-related disorders are caused by heterozygous mutations in FOXG1 and result in a spectrum of neurodevelopmental phenotypes including postnatal microcephaly, intellectual disability with absent speech, epilepsy, chorea, and corpus callosum abnormalities. The recurrence risk for de novo mutations in FOXG1-related disorders is assumed to be low. Here, we describe three unrelated sets of full siblings with mutations in FOXG1 (c.515_577del63, c.460dupG, and c.572T > G), representing familial recurrence of the disorder. In one family, we have documented maternal somatic mosaicism for the FOXG1 mutation, and all of the families presumably represent parental gonadal (or germline) mosaicism. To our knowledge, mosaicism has not been previously reported in FOXG1-related disorders. Therefore, this report provides evidence that germline mosaicism for FOXG1 mutations is a likely explanation for familial recurrence and should be considered during recurrence risk counseling for families of children with FOXG1-related disorders.
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Affiliation(s)
- Kelly Q McMahon
- Department of Neurology, University of Rochester Medical Center, Rochester, New York
| | - Apostolos Papandreou
- Developmental Neurosciences, UCL-Institute of Child Health, London, United Kingdom.,Department of Neurology, Great Ormond Street Hospital, London, United Kingdom.,Genetics and Genomics Medicine, UCL-Institute of Child Health, London, United Kingdom
| | - Mandy Ma
- University of Buffalo School of Medicine, Buffalo, New York
| | | | - Ghayda M Mirzaa
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington
| | - William B Dobyns
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington
| | - Richard H Scott
- Genetics and Genomics Medicine, UCL-Institute of Child Health, London, United Kingdom.,North East Thames Regional Genetics Service, Great Ormond Street Hospital, London, United Kingdom
| | - Natalie Trump
- North East Thames Regional Genetics Service, Great Ormond Street Hospital, London, United Kingdom
| | - Manju A Kurian
- Developmental Neurosciences, UCL-Institute of Child Health, London, United Kingdom.,Department of Neurology, Great Ormond Street Hospital, London, United Kingdom
| | - Alex R Paciorkowski
- Department of Neurology, University of Rochester Medical Center, Rochester, New York.,Departments of Pediatrics and Biomedical Genetics, Center for Neural Development and Disease, University of Rochester Medical Center, Rochester, New York
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Association of Tag SNPs and Rare CNVs of the MIR155HG/miR-155 Gene with Epilepsy in the Chinese Han Population. BIOMED RESEARCH INTERNATIONAL 2015; 2015:837213. [PMID: 26425555 PMCID: PMC4575730 DOI: 10.1155/2015/837213] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/28/2015] [Accepted: 07/09/2015] [Indexed: 01/12/2023]
Abstract
BACKGROUND miR-155 likely acts as an important modulator in the inflammatory mechanism of epilepsy, and this study investigated its association with epilepsy from the perspective of molecular genetics. METHODS This study enrolled 249 epileptic patients and 289 healthy individuals of the Chinese Han population; 4 tag single-nucleotide polymorphisms (SNPs: rs969885, rs12483428, rs987195, and rs4817027) of the MIR155HG/miR-155 gene were selected, and their association with epilepsy was investigated. Additionally, this study determined the copy numbers of the MIR155HG/miR-155 gene. RESULTS The TCA haplotype (rs12483428-rs987195-rs4817027) and the AA genotype at rs4817027 conferred higher vulnerability to epilepsy in males. Stratification by age of onset revealed that the CC haplotype (rs969885-rs987195) was a genetic susceptibility factor for early-onset epilepsy. Further stratification by drug-resistant status indicated the CC haplotype (rs969885-rs987195) and the AA genotype at rs4817027 were genetic susceptibility factors for drug-resistant epilepsy (DRE) but the CG haplotype (rs987195-rs969885) was a genetically protective factor against DRE. Besides, 3 epileptic patients with copy number variants of the MIR155HG/miR-155 gene were observed. CONCLUSIONS This study first demonstrates the association of MIR155HG/miR-155 tag SNPs with epilepsy and shows that rare CNVs were found exclusively in epileptic patients, clarifying the genetic role of miR-155 in epilepsy.
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Lee BH, Smith T, Paciorkowski AR. Autism spectrum disorder and epilepsy: Disorders with a shared biology. Epilepsy Behav 2015; 47:191-201. [PMID: 25900226 PMCID: PMC4475437 DOI: 10.1016/j.yebeh.2015.03.017] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 03/06/2015] [Accepted: 03/13/2015] [Indexed: 12/17/2022]
Abstract
There is an increasing recognition of clinical overlap in patients presenting with epilepsy and autism spectrum disorder (ASD), and a great deal of new information regarding the genetic causes of both disorders is available. Several biological pathways appear to be involved in both disease processes, including gene transcription regulation, cellular growth, synaptic channel function, and maintenance of synaptic structure. We review several genetic disorders where ASD and epilepsy frequently co-occur, and we discuss the screening tools available for practicing neurologists and epileptologists to help determine which patients should be referred for formal ASD diagnostic evaluation. Finally, we make recommendations regarding the workflow of genetic diagnostic testing available for children with both ASD and epilepsy. This article is part of a Special Issue entitled "Autism and Epilepsy".
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Affiliation(s)
- Bo Hoon Lee
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY, USA
| | - Tristram Smith
- Division of Neurodevelopmental and Behavioral Pediatrics, Department of Pediatrics, University of Rochester Medical Center, Rochester, NY, USA
| | - Alex R Paciorkowski
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY, USA; Department of Neurology, University of Rochester Medical Center, Rochester, NY, USA; Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY, USA; Center for Neural Development and Disease, University of Rochester Medical Center, Rochester, NY, USA.
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Bitton JY, Demos M, Elkouby K, Connolly M, Weiss SK, Donner EJ, Whiting S, Ronen GM, Bello-Espinosa L, Wirrell EC, Mohamed IS, Dooley JM, Carmant L. Does treatment have an impact on incidence and risk factors for autism spectrum disorders in children with infantile spasms? Epilepsia 2015; 56:856-63. [PMID: 25944453 DOI: 10.1111/epi.12997] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2015] [Indexed: 01/01/2023]
Abstract
OBJECTIVE Infantile spasms (IS) are a severe form of childhood epilepsy associated with autism spectrum disorders (ASD) in up to 35% of cases. The objective of this post hoc analysis of our randomized control trial was to determine whether rapid diagnosis and treatment of IS could limit the incidence of ASD while identifying risk factors related to ASD outcome. METHODS Patients with IS were randomized in a standardized diagnostic and treatment protocol. Clinical and electroencephalogram (EEG) evaluations were completed at all eight visits over 5 years, while cognitive evaluations were administered at 0, 6, 24 and 60 months, respectively. Autism was initially screened by means of the Checklist for Autism in Toddlers (CHAT) at 24 months, and formally assessed at the 30-and 60-month follow-ups using the Autism Diagnostic Observation Schedule-Generic (ADOS-G). RESULTS Of the 69 patients included in the study, 25 could not be assessed due to severe delay or death. Eleven of the 42 patients screened with CHAT, were found to be at risk of an ASD outcome. ADOS was performed in 44 and 10 were diagnosed with ASD. The CHAT proved to correlate highly with the ADOS (80% ppv). Only patients with symptomatic IS developed ASD (p = 0.003). Earlier diagnosis or successful treatment did not correlate with a reduced rate of ASD. Other risk factors were identified such as having chronic epileptic discharges in the frontotemporal areas after disappearance of hypsarrhythmia (p = 0.005 and p = 0.007) and being of nonwhite origin (p = 0.009). SIGNIFICANCE ASD was only observed in children with sympyomatic IS. Other clinical risk factors include chronic frontotemporal epileptic activity and being of non-white origin. Early diagnosis and treatment did not prevent ASD as an outcome of IS. However, patients at risk for ASD could be identified early on and should in the future benefit from early intervention to potentially improve their long-term outcome.
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Affiliation(s)
- Jonathan Y Bitton
- Research Centre and Division of Neurology, Department of Pediatrics, Sainte-Justine Hospital (CHU Sainte-Justine), Montreal, Quebec, Canada
| | - Michelle Demos
- Division of Neurology, Department of Pediatrics, Faculty of Medicine, BC Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Katia Elkouby
- Research Centre and Division of Neurology, Department of Pediatrics, Sainte-Justine Hospital (CHU Sainte-Justine), Montreal, Quebec, Canada
| | - Mary Connolly
- Division of Neurology, Department of Pediatrics, Faculty of Medicine, BC Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Shelly K Weiss
- Division of Neurology, Department of Pediatrics, Faculty of Medicine, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Elizabeth J Donner
- Division of Neurology, Department of Pediatrics, Faculty of Medicine, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Sharon Whiting
- Division of Neurology, Department of Pediatrics, Faculty of Medicine, Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, Ontario, Canada
| | - Gabriel M Ronen
- Division of Neurology, Department of Pediatrics, Faculty of Medicine, McMaster Health Sciences Centre, McMaster University, Hamilton, Ontario, Canada
| | - Luis Bello-Espinosa
- Division of Neurology, Department of Pediatrics, Faculty of Medicine, Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | - Elaine C Wirrell
- Division of Neurology, Department of Pediatrics, Faculty of Medicine, Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada.,Division of Child and Adolescent Neurology, Mayo Clinic, Rochester, Minnesota, U.S.A
| | - Ismail S Mohamed
- Division of Neurology, Department of Pediatrics, Faculty of Medicine, Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada.,Division of Neurology, Department of Pediatrics, Faculty of Medicine, Izaak Walton Killam (IWK) Health Centre, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Joseph M Dooley
- Division of Neurology, Department of Pediatrics, Faculty of Medicine, Izaak Walton Killam (IWK) Health Centre, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Lionel Carmant
- Research Centre and Division of Neurology, Department of Pediatrics, Sainte-Justine Hospital (CHU Sainte-Justine), Montreal, Quebec, Canada
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40
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The clustering of functionally related genes contributes to CNV-mediated disease. Genome Res 2015; 25:802-13. [PMID: 25887030 PMCID: PMC4448677 DOI: 10.1101/gr.184325.114] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 04/13/2015] [Indexed: 12/20/2022]
Abstract
Clusters of functionally related genes can be disrupted by a single copy number variant (CNV). We demonstrate that the simultaneous disruption of multiple functionally related genes is a frequent and significant characteristic of de novo CNVs in patients with developmental disorders (P = 1 × 10−3). Using three different functional networks, we identified unexpectedly large numbers of functionally related genes within de novo CNVs from two large independent cohorts of individuals with developmental disorders. The presence of multiple functionally related genes was a significant predictor of a CNV's pathogenicity when compared to CNVs from apparently healthy individuals and a better predictor than the presence of known disease or haploinsufficient genes for larger CNVs. The functionally related genes found in the de novo CNVs belonged to 70% of all clusters of functionally related genes found across the genome. De novo CNVs were more likely to affect functional clusters and affect them to a greater extent than benign CNVs (P = 6 × 10−4). Furthermore, such clusters of functionally related genes are phenotypically informative: Different patients possessing CNVs that affect the same cluster of functionally related genes exhibit more similar phenotypes than expected (P < 0.05). The spanning of multiple functionally similar genes by single CNVs contributes substantially to how these variants exert their pathogenic effects.
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41
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Genomic analysis identifies candidate pathogenic variants in 9 of 18 patients with unexplained West syndrome. Hum Genet 2015; 134:649-58. [DOI: 10.1007/s00439-015-1553-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 04/06/2015] [Indexed: 01/10/2023]
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Lukose R, Beebe K, Kulesza RJ. Organization of the human superior olivary complex in 15q duplication syndromes and autism spectrum disorders. Neuroscience 2014; 286:216-30. [PMID: 25484361 DOI: 10.1016/j.neuroscience.2014.11.033] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 10/30/2014] [Accepted: 11/13/2014] [Indexed: 10/24/2022]
Abstract
Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by a number of behavioral and social features. Although the etiology of most cases of ASD is idiopathic, a significant number of cases can be attributed to genetic causes, such as chromosome 15q duplications [dup(15q)]. Recent neuropathological investigations have provided evidence for distinct patterns of heterotopias and dysplasias in ASD and subjects with both ASD and dup(15q). Individuals with ASD characteristically have hearing difficulties and we have previously demonstrated significant and consistent hypoplasia in a number of auditory brainstem nuclei in subjects with ASD. Herein, we compare results from a morphometric investigation of auditory brainstem nuclei in subjects with ASD, dup(15q) and controls. Our observations in subjects with ASD support our previous reports. However, in subjects with dup(15q), we find significantly fewer neurons and in many nuclei, neurons were significantly smaller than in ASD subjects. Finally, we find a notably higher incidence of ectopic neurons in dup(15q). These results suggest that in the brainstem, these neuropathological conditions may evolve from some of the same developmental errors but are distinguished on microscopic features.
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Affiliation(s)
- R Lukose
- University of Pittsburgh Medical Center - Hamot, Department of Neurology, United States
| | - K Beebe
- Lake Erie College of Osteopathic Medicine, Department of Anatomy, United States
| | - R J Kulesza
- Lake Erie College of Osteopathic Medicine, Department of Anatomy, United States.
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Olson HE, Poduri A, Pearl PL. Genetic forms of epilepsies and other paroxysmal disorders. Semin Neurol 2014; 34:266-79. [PMID: 25192505 DOI: 10.1055/s-0034-1386765] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Genetic mechanisms explain the pathophysiology of many forms of epilepsy and other paroxysmal disorders, such as alternating hemiplegia of childhood, familial hemiplegic migraine, and paroxysmal dyskinesias. Epilepsy is a key feature of well-defined genetic syndromes including tuberous sclerosis complex, Rett syndrome, Angelman syndrome, and others. There is an increasing number of single-gene causes or susceptibility factors associated with several epilepsy syndromes, including the early-onset epileptic encephalopathies, benign neonatal/infantile seizures, progressive myoclonus epilepsies, genetic generalized and benign focal epilepsies, epileptic aphasias, and familial focal epilepsies. Molecular mechanisms are diverse, and a single gene can be associated with a broad range of phenotypes. Additional features, such as dysmorphisms, head size, movement disorders, and family history may provide clues to a genetic diagnosis. Genetic testing can impact medical care and counseling. We discuss genetic mechanisms of epilepsy and other paroxysmal disorders, tools and indications for genetic testing, known genotype-phenotype associations, the importance of genetic counseling, and a look toward the future of epilepsy genetics.
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Affiliation(s)
- Heather E Olson
- Division of Epilepsy, Department of Neurology, Boston Children's Hospital, Boston, Massachusetts
| | - Annapurna Poduri
- Division of Epilepsy, Department of Neurology, Boston Children's Hospital, Boston, Massachusetts
| | - Phillip L Pearl
- Division of Epilepsy, Department of Neurology, Boston Children's Hospital, Boston, Massachusetts
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44
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Du X, An Y, Yu L, Liu R, Qin Y, Guo X, Sun D, Zhou S, Wu B, Jiang YH, Wang Y. A genomic copy number variant analysis implicates the MBD5 and HNRNPU genes in Chinese children with infantile spasms and expands the clinical spectrum of 2q23.1 deletion. BMC MEDICAL GENETICS 2014; 15:62. [PMID: 24885232 PMCID: PMC4061518 DOI: 10.1186/1471-2350-15-62] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 05/13/2014] [Indexed: 02/06/2023]
Abstract
Background Infantile spasms (IS) is a specific type of epileptic encephalopathy associated with severe developmental disabilities. Genetic factors are strongly implicated in IS, however, the exact genetic defects remain unknown in the majority of cases. Rare mutations in a single gene or in copy number variants (CNVs) have been implicated in IS of children in Western countries. The objective of this study was to dissect the role of copy number variations in Chinese children with infantile spasms. Methods We used the Agilent Human Genome CGH microarray 180 K for genome-wide detection of CNVs. Real-time qPCR was used to validate the CNVs. We performed genomic and medical annotations for individual CNVs to determine the pathogenicity of CNVs related to IS. Results We report herein the first genome-wide CNV analysis in children with IS, detecting a total of 14 CNVs in a cohort of 47 Chinese children with IS. Four CNVs (4/47 = 8.5%) (1q21.1 gain; 1q44, 2q31.1, and 17p13 loss) are considered to be pathogenic. The CNV loss at 17p13.3 contains PAFAH1B1 (LIS1), a causative gene for lissencephaly. Although the CNVs at 1q21.1, 1q44, and 2q23.1 have been previously implicated in a wide spectrum of clinical features including autism spectrum disorders (ASD) and generalized seizure, our study is the first report identifying them in individuals with a primary diagnosis of IS. The CNV loss in the 1q44 region contains HNRNPU, a strong candidate gene recently suggested in IS by the whole exome sequencing of children with IS. The CNV loss at 2q23.1 includes MBD5, a methyl-DNA binding protein that is a causative gene of ASD and a candidate gene for epileptic encephalopathy. We also report a distinct clinical presentation of IS, microcephaly, intellectual disability, and absent hallux in a case with the 2q23.1 deletion. Conclusion Our findings strongly support the role of CNVs in infantile spasms and expand the clinical spectrum associate with 2q23.1 deletion. In particular, our study implicates the HNRNPU and MBD5 genes in Chinese children with IS. Our study also supports that the molecular mechanisms of infantile spasms appear conserved among different ethnic backgrounds.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Yong-Hui Jiang
- Division of Neurology, Children's Hospital of Fudan University, 399 Wan Yuan Road, Shanghai 201102, China.
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Seltzer LE, Ma M, Ahmed S, Bertrand M, Dobyns WB, Wheless J, Paciorkowski AR. Epilepsy and outcome in FOXG1-related disorders. Epilepsia 2014; 55:1292-300. [PMID: 24836831 DOI: 10.1111/epi.12648] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/02/2014] [Indexed: 12/18/2022]
Abstract
OBJECTIVE FOXG1-related disorders are associated with severe intellectual disability, absent speech with autistic features, and epilepsy. Children with deletions or intragenic mutations of FOXG1 also have postnatal microcephaly, morphologic abnormalities of the corpus callosum, and choreiform movements. Duplications of 14q12 often present with infantile spasms, and have subsequent intellectual disability with autistic features. Long-term epilepsy outcome and response to treatment have not been studied systematically in a well-described cohort of subjects with FOXG1-related disorders. We report on the epilepsy features and developmental outcome of 23 new subjects with deletions or intragenic mutations of FOXG1, and 7 subjects with duplications. METHODS Subjects had either chromosomal microarray or FOXG1 gene sequencing performed as part of routine clinical care. Development and epilepsy follow-up data were collected from medical records from treating neurologists and through telephone parental interviews using standardized questionnaires. RESULTS Epilepsy was diagnosed in 87% of the subjects with FOXG1-related disorders. The mean age of epilepsy diagnosis in FOXG1 duplications was significantly younger than those with deletions/intragenic mutations (p = 0.0002). All of the duplication FOXG1 children with infantile spasms responded to hormonal therapy, and only one required long-term antiepileptic therapy. In contrast, more children with deletions/intragenic mutations required antiepileptic drugs on follow-up (p < 0.0005). All subjects with FOXG1-related disorders had neurodevelopmental disabilities after 3 years of age, regardless of the epilepsy type or intractability of seizures. All had impaired verbal language and social contact, and three duplication subjects were formally diagnosed with autism. Subjects with deletion/intragenic mutations, however, had significantly worse ambulation (p = 0.04) and functional hand use (p < 0.0005). SIGNIFICANCE Epilepsy and developmental outcome characteristics allow clinicians to distinguish among the FOXG1-related disorders. Further genotype-phenotype studies of FOXG1 may help to elucidate why children develop different forms of developmental epilepsy.
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Affiliation(s)
- Laurie E Seltzer
- Department of Neurology, University of Rochester Medical Center, Rochester, New York, U.S.A
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46
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6q22.1 microdeletion and susceptibility to pediatric epilepsy. Eur J Hum Genet 2014; 23:173-9. [PMID: 24824130 DOI: 10.1038/ejhg.2014.75] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 03/04/2014] [Accepted: 03/07/2014] [Indexed: 12/31/2022] Open
Abstract
Genomic copy-number variations (CNVs) constitute an important cause of epilepsies and other human neurological disorders. Recent advancement of technologies integrating genome-wide CNV mapping and sequencing is rapidly expanding the molecular field of pediatric neurodevelopmental disorders. In a previous study, a novel epilepsy locus was identified on 6q16.3q22.31 by linkage analysis in a large pedigree. Subsequent array comparative genomic hybridization (array CGH) analysis of four unrelated cases narrowed this region to ∼5 Mb on 6q22.1q22.31. We sought to further narrow the critical region on chromosome 6q22. Array CGH analysis was used in genome-wide screen for CNVs of a large cohort of patients with neurological abnormalities. Long-range PCR and DNA sequencing were applied to precisely map chromosomal deletion breakpoints. Finally, real-time qPCR was used to estimate relative expression in the brain of the candidate genes. We identified six unrelated patients with overlapping microdeletions within 6q22.1q22.31 region, three of whom manifested seizures. Deletions were found to be de novo in 5/6 cases, including all subjects presenting with seizures. We sequenced the deletion breakpoints in four patients and narrowed the critical region to a ∼250-kb segment at 6q22.1 that includes NUS1, several expressed sequence tags (ESTs) that are highly expressed in the brain, and putative regulatory sequences of SLC35F1. Our findings indicate that dosage alteration in particular, of NUS1, EST AI858607, or SLC35F1 are important contributors to the neurodevelopmental phenotype associated with 6q22 deletion, including epilepsy and tremors.
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47
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Pontrelli G, Cappelletti S, Claps D, Sirleto P, Ciocca L, Petrocchi S, Terracciano A, Serino D, Fusco L, Vigevano F, Specchio N. Epilepsy in patients with duplications of chromosome 14 harboring FOXG1. Pediatr Neurol 2014; 50:530-5. [PMID: 24731847 DOI: 10.1016/j.pediatrneurol.2014.01.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 12/16/2013] [Accepted: 01/05/2014] [Indexed: 01/09/2023]
Abstract
BACKGROUND Dup(14q12) harboring FOXG1 has been recently reported in individuals with developmental delay of variable severity, delayed/absent speech, and epilepsy/infantile spasms. FOXG1 was described as a dosage-sensitive gene encoding G1, a forkhead protein that is a brain-specific transcription factor with a role in brain development. PATIENTS We extensively reviewed all published cases with dup(14) harboring FOXG1 and highlighted those epileptological features that are more commonly found among such cases. We also describe one new patient, detailing his peculiar clinical and neurophysiological findings. RESULTS To date, 15 patients with dup(14) including FOXG1 have been reported; within those patients, nine also presented with epilepsy. At onset, the more frequent seizure type in the report and also in our patient is the epileptic spasm. Focal seizures might also be present. Outcomes in patients with epilepsy associated with dup(14) should be considered separately regarding seizures and cognitive and motor development. In the majority of patients (seven of 10, including ours), seizures tend to disappear and motor skills improve; however, instead stagnation of cognitive development is evident in all of them, associated with severe speech difficulties. CONCLUSIONS There are some common features that should be considered: seizures with onset during the first year of life, particularly clusters of spasms and focal seizures with hypsarrhythmic electroencephalograph pattern; different degrees of cognitive impairment possibly associated with behavior disturbances and severe speech disabilities; and dysmorphic features in the absence of significant microcephaly.
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Affiliation(s)
- Giuseppe Pontrelli
- Division of Neurology, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy; "Amaducci" Neurology Unit, Department of Neuroscience, University of Bari, Bari, Italy
| | - Simona Cappelletti
- Unit of Clinical Psychology, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Dianela Claps
- Division of Neurology, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Pietro Sirleto
- Cytogenetics and Molecular Genetics Unit, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Laura Ciocca
- Cytogenetics and Molecular Genetics Unit, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Stefano Petrocchi
- Cytogenetics and Molecular Genetics Unit, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Alessandra Terracciano
- Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Diseases, Bambino Gesú Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Domenico Serino
- Division of Neurology, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Lucia Fusco
- Division of Neurology, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Federico Vigevano
- Division of Neurology, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Nicola Specchio
- Division of Neurology, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.
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Õiglane-Shlik E, Puusepp S, Talvik I, Vaher U, Rein R, Tammur P, Reimand T, Teek R, Žilina O, Tomberg T, Õunap K. Monosomy 1p36 - a multifaceted and still enigmatic syndrome: four clinically diverse cases with shared white matter abnormalities. Eur J Paediatr Neurol 2014; 18:338-46. [PMID: 24529875 DOI: 10.1016/j.ejpn.2014.01.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 01/05/2014] [Accepted: 01/19/2014] [Indexed: 10/25/2022]
Abstract
Monosomy 1p36 is the most common subtelomeric deletion syndrome seen in humans. Uniform features of the syndrome include early developmental delay and consequent intellectual disability, muscular hypotonia, and characteristic dysmorphic facial features. The gene-rich nature of the chromosomal band, inconsistent deletion sizes and overlapping clinical features have complicated relevant genotype-phenotype correlations. We describe four patients with isolated chromosome 1p36 deletions. All patients shared white matter abnormalities, allowing us to narrow the critical region for white matter involvement to the deletion size of up to 2.5 Mb from the telomere. We hypothesise that there might be a gene(s) responsible for myelin development in the 1p36 subtelomeric region. Other significant clinical findings were progressive spastic paraparesis, epileptic encephalopathy, various skeletal anomalies, Prader-Willi-like phenotype, neoplastic changes - a haemangioma and a benign skin tumour, and in one case, sleep myoclonus, a clinical entity not previously described in association with 1p36 monosomy. Combined with prior studies, our results suggest that the clinical features seen in monosomy 1p36 have more complex causes than a classical contiguous gene deletion syndrome.
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Affiliation(s)
- Eve Õiglane-Shlik
- Department of Pediatrics, Faculty of Medicine, University of Tartu, Tartu, Estonia; Children's Clinic, Tartu University Hospital, Tartu, Estonia.
| | - Sanna Puusepp
- Faculty of Medicine, University of Tartu, Tartu, Estonia
| | - Inga Talvik
- Department of Pediatrics, Faculty of Medicine, University of Tartu, Tartu, Estonia; Children's Clinic, Tartu University Hospital, Tartu, Estonia
| | - Ulvi Vaher
- Children's Clinic, Tartu University Hospital, Tartu, Estonia
| | - Reet Rein
- Children's Clinic, Tartu University Hospital, Tartu, Estonia
| | - Pille Tammur
- Department of Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
| | - Tiia Reimand
- Department of Pediatrics, Faculty of Medicine, University of Tartu, Tartu, Estonia; Department of Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia; Department of Biomedicine, Institute of Biomedicine and Centre for Translational Medicine, University of Tartu, Tartu, Estonia
| | - Rita Teek
- Department of Pediatrics, Faculty of Medicine, University of Tartu, Tartu, Estonia; Department of Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
| | - Olga Žilina
- Department of Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia; Department of Biotechnology, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
| | - Tiiu Tomberg
- Department of Neurology and Neurosurgery, Faculty of Medicine, University of Tartu, Tartu, Estonia
| | - Katrin Õunap
- Department of Pediatrics, Faculty of Medicine, University of Tartu, Tartu, Estonia; Department of Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
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Bertossi C, Cassina M, De Palma L, Vecchi M, Rossato S, Toldo I, Donà M, Murgia A, Boniver C, Sartori S. 14q12 duplication including FOXG1: is there a common age-dependent epileptic phenotype? Brain Dev 2014; 36:402-7. [PMID: 23838309 DOI: 10.1016/j.braindev.2013.06.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 06/11/2013] [Accepted: 06/12/2013] [Indexed: 11/17/2022]
Abstract
INTRODUCTION Duplications of 14q12 encompassing FOXG1 gene have been recently associated with developmental delay, severe speech impairment, epilepsy, aspecific neuroimaging findings and minor dysmorphisms. AIM AND METHODS In order to refine the epileptic phenotype associated with 14q12 duplications, we have performed a review of the electroclinical picture of the patients reported to date in the literature, adding a new personal case. A comprehensive set of clinical and instrumental data (with a particular focus on the electroclinical aspects including seizure type, age of onset, EEG at onset and after antiepileptic therapy, drug efficacy) has been taken into account. RESULTS 9/14 patients carrying 14q12 duplications developed seizures, all in the first months of life. Most of them developed infantile spasms (8/9 epileptic patients) and presented hypsarrhythmia or modified hypsarrhythmia on EEG. After therapy 5/9 patients became seizure free and 3/9 present a good seizure control. At last available follow up, 2/3 of the epileptic patients displayed an almost normal EEG, or a quite organized background activity, with diffuse or focal (mostly temporal) slowing. CONCLUSIONS The review of the available data allowed to recognize a common epileptic core, characterized by early onset, age dependent epileptic encephalopathy with infantile spasms and typical, atypical or modified hypsarrhythmia. Antiepileptic therapy soon led to a good or complete control of seizures with a nearly normal background activity in most patients.
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Affiliation(s)
- Chiara Bertossi
- Pediatric Neurology Unit, Department of Women's and Children's Health, University of Padua, Italy
| | - Matteo Cassina
- Clinical Genetics Unit, Department of Women's and Children's Health, University of Padua, Italy
| | - Luca De Palma
- Pediatric Neurology Unit, Department of Women's and Children's Health, University of Padua, Italy
| | - Marilena Vecchi
- Pediatric Neurology Unit, Department of Women's and Children's Health, University of Padua, Italy
| | | | - Irene Toldo
- Pediatric Neurology Unit, Department of Women's and Children's Health, University of Padua, Italy
| | - Marta Donà
- Clinical Genetics Unit, Department of Women's and Children's Health, University of Padua, Italy
| | - Alessandra Murgia
- Pediatric Neurology Unit, Department of Women's and Children's Health, University of Padua, Italy
| | - Clementina Boniver
- Pediatric Neurology Unit, Department of Women's and Children's Health, University of Padua, Italy
| | - Stefano Sartori
- Pediatric Neurology Unit, Department of Women's and Children's Health, University of Padua, Italy.
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50
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Conant KD, Finucane B, Cleary N, Martin A, Muss C, Delany M, Murphy EK, Rabe O, Luchsinger K, Spence SJ, Schanen C, Devinsky O, Cook EH, LaSalle J, Reiter LT, Thibert RL. A survey of seizures and current treatments in 15q duplication syndrome. Epilepsia 2014; 55:396-402. [PMID: 24502430 DOI: 10.1111/epi.12530] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/26/2013] [Indexed: 01/05/2023]
Abstract
OBJECTIVE Seizures are common in individuals with duplications of chromosome 15q11.2-q13 (Dup15q). The goal of this study was to examine the phenotypes and treatments of seizures in Dup15q in a large population. METHODS A detailed electronic survey was conducted through the Dup15q Alliance containing comprehensive questions regarding seizures and their treatments in Dup15q. RESULTS There were 95 responses from Dup15q families. For the 83 with idic(15), 63% were reported to have seizures, of which 81% had multiple seizure types and 42% had infantile spasms. Other common seizure types were tonic-clonic, atonic, myoclonic, and focal. Only 3 of 12 individuals with int dup(15) had seizures. Broad spectrum antiepileptic drugs (AEDs) were the most effective medications, but carbamazepine and oxcarbazepine were also effective, although typical benzodiazepines were relatively ineffective. There was a 24% response rate (>90% seizure reduction) to the first AED tried. For those with infantile spasms, adrenocorticotropic hormone (ACTH) was more effective than vigabatrin. SIGNIFICANCE This is the largest study assessing seizures in Duplication 15q syndrome, but because this was a questionnaire-based study with a low return rate, it is susceptible to bias. Seizures are common in idic(15) and typically difficult to control, often presenting with infantile spasms and progressing to a Lennox-Gastaut-type syndrome. Seizures in those with int dup(15) are less common, with a frequency similar to the general autism population. In addition to broad spectrum AED, medications such as carbamazepine and oxcarbazepine are also relatively effective in controlling seizures in this population, suggesting a possible multifocal etiology, which may also explain the high rate of infantile spasms. Our small sample suggests a relative lack of efficacy of vigabatrin and other γ-aminobutyric acid (GABA)ergic medications, such as typical benzodiazepines, which may be attributable to abnormal GABAergic transmission resulting from the duplication of a cluster of GABAβ3 receptor genes in the 15q11.2-13 region.
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Affiliation(s)
- Kerry D Conant
- Pediatric Epilepsy Program, Massachusetts General Hospital, Boston, Massachusetts, U.S.A
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