1
|
Rots D, Choufani S, Faundes V, Dingemans AJM, Joss S, Foulds N, Jones EA, Stewart S, Vasudevan P, Dabir T, Park SM, Jewell R, Brown N, Pais L, Jacquemont S, Jizi K, Ravenswaaij-Arts CMAV, Kroes HY, Stumpel CTRM, Ockeloen CW, Diets IJ, Nizon M, Vincent M, Cogné B, Besnard T, Kambouris M, Anderson E, Zackai EH, McDougall C, Donoghue S, O'Donnell-Luria A, Valivullah Z, O'Leary M, Srivastava S, Byers H, Leslie N, Mazzola S, Tiller GE, Vera M, Shen JJ, Boles R, Jain V, Brischoux-Boucher E, Kinning E, Simpson BN, Giltay JC, Harris J, Keren B, Guimier A, Marijon P, Vries BBAD, Motter CS, Mendelsohn BA, Coffino S, Gerkes EH, Afenjar A, Visconti P, Bacchelli E, Maestrini E, Delahaye-Duriez A, Gooch C, Hendriks Y, Adams H, Thauvin-Robinet C, Josephi-Taylor S, Bertoli M, Parker MJ, Rutten JW, Caluseriu O, Vernon HJ, Kaziyev J, Zhu J, Kremen J, Frazier Z, Osika H, Breault D, Nair S, Lewis SME, Ceroni F, Viggiano M, Posar A, Brittain H, Giovanna T, Giulia G, Quteineh L, Ha-Vinh Leuchter R, Zonneveld-Huijssoon E, Mellado C, Marey I, Coudert A, Aracena Alvarez MI, Kennis MGP, Bouman A, Roifman M, Amorós Rodríguez MI, Ortigoza-Escobar JD, Vernimmen V, Sinnema M, Pfundt R, Brunner HG, Vissers LELM, Kleefstra T, Weksberg R, Banka S. Pathogenic variants in KMT2C result in a neurodevelopmental disorder distinct from Kleefstra and Kabuki syndromes. Am J Hum Genet 2024; 111:1626-1642. [PMID: 39013459 PMCID: PMC11339626 DOI: 10.1016/j.ajhg.2024.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 06/08/2024] [Accepted: 06/19/2024] [Indexed: 07/18/2024] Open
Abstract
Trithorax-related H3K4 methyltransferases, KMT2C and KMT2D, are critical epigenetic modifiers. Haploinsufficiency of KMT2C was only recently recognized as a cause of neurodevelopmental disorder (NDD), so the clinical and molecular spectrums of the KMT2C-related NDD (now designated as Kleefstra syndrome 2) are largely unknown. We ascertained 98 individuals with rare KMT2C variants, including 75 with protein-truncating variants (PTVs). Notably, ∼15% of KMT2C PTVs were inherited. Although the most highly expressed KMT2C transcript consists of only the last four exons, pathogenic PTVs were found in almost all the exons of this large gene. KMT2C variant interpretation can be challenging due to segmental duplications and clonal hematopoesis-induced artifacts. Using samples from 27 affected individuals, divided into discovery and validation cohorts, we generated a moderate strength disorder-specific KMT2C DNA methylation (DNAm) signature and demonstrate its utility in classifying non-truncating variants. Based on 81 individuals with pathogenic/likely pathogenic variants, we demonstrate that the KMT2C-related NDD is characterized by developmental delay, intellectual disability, behavioral and psychiatric problems, hypotonia, seizures, short stature, and other comorbidities. The facial module of PhenoScore, applied to photographs of 34 affected individuals, reveals that the KMT2C-related facial gestalt is significantly different from the general NDD population. Finally, using PhenoScore and DNAm signatures, we demonstrate that the KMT2C-related NDD is clinically and epigenetically distinct from Kleefstra and Kabuki syndromes. Overall, we define the clinical features, molecular spectrum, and DNAm signature of the KMT2C-related NDD and demonstrate they are distinct from Kleefstra and Kabuki syndromes highlighting the need to rename this condition.
Collapse
Affiliation(s)
- Dmitrijs Rots
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands; Department of Clinical Genetics, Erasmus MC, Rotterdam, the Netherlands; Genetics Laboratory, Children's Clinical University Hospital, Riga, Latvia
| | - Sanaa Choufani
- Genetics and Genome Biology Program, Research Institute, the Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | - Victor Faundes
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de Los Alimentos (INTA), Universidad de Chile, Santiago, Chile; Manchester Centre for Genomic Medicine, Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | | | - Shelagh Joss
- West of Scotland Centre for Genomic Medicine, Queen Elizabeth University Hospital, Glasgow, UK
| | - Nicola Foulds
- Wessex Clinical Genetics Services, University Hospital Southampton NHS Foundation Trust, Southampton SO16 5YA, UK
| | - Elizabeth A Jones
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester, Manchester, UK; Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Sarah Stewart
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester, Manchester, UK
| | - Pradeep Vasudevan
- Department of Clinical Genetics, University Hospitals of Leicester, Leicester Royal Infirmary, Leicester LE1 7RH, UK
| | - Tabib Dabir
- Northern Ireland Regional Genetics Centre, Belfast City Hospital, Belfast, UK
| | - Soo-Mi Park
- Department of Clinical Genetics, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Rosalyn Jewell
- Yorkshire Regional Genetics Service, Chapel Allerton Hospital, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Natasha Brown
- Victorian Clinical Genetics Service, Murdoch Children's Research Institute, Melbourne, VIC, Australia; Department of Paediatrics, Royal Children's Hospital, The University of Melbourne, Melbourne, VIC, Australia
| | - Lynn Pais
- Center for Mendelian Genomics, Broad Institute of MIT and Harvard, Cambridge, MA, USA; Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Khadijé Jizi
- Service de Génétique Médicale, CHU Ste-Justine, Montréal, QC, Canada
| | | | - Hester Y Kroes
- Division Laboratories, Pharmacy and Biomedical Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Constance T R M Stumpel
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, the Netherlands; GROW-School for Oncology and Reproduction, Maastricht, the Netherlands
| | - Charlotte W Ockeloen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Illja J Diets
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Mathilde Nizon
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Marie Vincent
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Benjamin Cogné
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Thomas Besnard
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Marios Kambouris
- Division of Genetics, Department of Pathology and Laboratory Medicine Department, Sidra Medicine, Doha, Qatar
| | - Emily Anderson
- Liverpool Centre for Genomic Medicine, Liverpool Women's NHS Foundation Trust, Liverpool, UK
| | - Elaine H Zackai
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Carey McDougall
- Division of Human Genetics, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Sarah Donoghue
- Division of Human Genetics, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Anne O'Donnell-Luria
- Center for Mendelian Genomics, Broad Institute of MIT and Harvard, Cambridge, MA, USA; Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Zaheer Valivullah
- Center for Mendelian Genomics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Melanie O'Leary
- Center for Mendelian Genomics, Broad Institute of MIT and Harvard, Cambridge, MA, USA; Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA
| | | | - Heather Byers
- Department of Pediatrics, Stanford University, Stanford, CA, USA
| | - Nancy Leslie
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Sarah Mazzola
- Center for Personalized Genetic Healthcare, Cleveland Clinic, Cleveland, OH, USA
| | - George E Tiller
- Department of Genetics, Kaiser Permanente, Los Angeles, CA, USA
| | - Moin Vera
- Department of Genetics, Kaiser Permanente, Los Angeles, CA, USA
| | - Joseph J Shen
- Division of Genetics, Department of Pediatrics, UCSF Fresno, Fresno, CA, USA; Division of Genomic Medicine, Department of Pediatrics, University of California Davis, Sacramento, CA, USA
| | | | - Vani Jain
- All Wales Medical Genomics Service, Wales Genomic Health Centre, Cardiff Edge Business Park, Longwood Drive, Whitchurch, Cardiff CF14 7YU, UK
| | | | - Esther Kinning
- Clinical Genetics, Birmingham Women's and Children's, Birmingham, UK
| | - Brittany N Simpson
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Department of Pediatrics, University of Cincinnati, Cincinnati, OH, USA
| | - Jacques C Giltay
- Division Laboratories, Pharmacy and Biomedical Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Jacqueline Harris
- Kennedy Krieger Institute, Baltimore, MD, USA; Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Boris Keren
- Department of Genetics, APHP Sorbonne University, Paris, France
| | - Anne Guimier
- Service de Médecine Genomique des Maladies Rares, CRMR Anomalies Du Développement, Hôpital Necker-Enfants Malades, Assistance Publique des Hôpitaux de Paris, Paris, France
| | - Pierre Marijon
- Laboratoire de Biologie Médicale Multisites Seqoia FMG2025, 75014 Paris, France
| | - Bert B A de Vries
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | | | | | - Samantha Coffino
- Department of Pediatric Neurology, Kaiser Permanente, Oakland, CA, USA
| | - Erica H Gerkes
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Alexandra Afenjar
- APHP Sorbonne Université, Centre de Référence Malformations et Maladies Congénitales Du Cervelet et Déficiences Intellectuelles de Causes Rares, Département de Génétique et Embryologie Médicale, Hôpital Trousseau, Paris, France
| | - Paola Visconti
- IRCCS Istituto Delle Scienze Neurologiche di Bologna, UOSI Disturbi Dello Spettro Autistico, Bologna, Italy
| | - Elena Bacchelli
- Pharmacy and Biotechnology Department, University of Bologna, Bologna, Italy
| | - Elena Maestrini
- Pharmacy and Biotechnology Department, University of Bologna, Bologna, Italy
| | | | - Catherine Gooch
- Division of Genetics and Genomic Medicine, Department of Pediatrics, Washington University School of Medicine, St Louis, MO, USA
| | - Yvonne Hendriks
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Hieab Adams
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands; Department of Clinical Genetics, Erasmus MC, Rotterdam, the Netherlands
| | - Christel Thauvin-Robinet
- Unité Fonctionnelle Innovation en Diagnostic Génomique des Maladies Rares, Dijon, France; Inserm, UMR1231, Equipe GAD, Bâtiment B3, Université de Bourgogne Franche Comté, Dijon Cedex, France; Centre de Référence Déficiences Intellectuelles de Causes Rares, FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France
| | - Sarah Josephi-Taylor
- Department of Clinical Genetics, The Children's Hospital at Westmead, Sydney, NSW, Australia; Discipline of Genomic Medicine, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Marta Bertoli
- Northern Genetics Service, Newcastle Upon Tyne NHS Foundation Trust, Newcastle Upon Tyne, UK
| | - Michael J Parker
- Department of Clinical Genetics, Sheffield Children's Hospital, Sheffield, UK
| | - Julie W Rutten
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Oana Caluseriu
- Department of Medical Genetics, University of Alberta, Edmonton, Canada
| | - Hilary J Vernon
- Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jonah Kaziyev
- Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Jia Zhu
- Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Jessica Kremen
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Zoe Frazier
- Rosamund Stone Zander Translational Neuroscience Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Hailey Osika
- Rosamund Stone Zander Translational Neuroscience Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - David Breault
- Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Sreelata Nair
- Department of Fetal Medicine, Lifeline Super Specialty Hospital, Kerala, India
| | - Suzanne M E Lewis
- Department of Medical Genetics, BC Children's Hospital Research Institute, The University of British Columbia, Vancouver, BC, Canada
| | - Fabiola Ceroni
- Pharmacy and Biotechnology Department, University of Bologna, Bologna, Italy; Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK
| | - Marta Viggiano
- Pharmacy and Biotechnology Department, University of Bologna, Bologna, Italy
| | - Annio Posar
- IRCCS Istituto Delle Scienze Neurologiche di Bologna, UOSI Disturbi Dello Spettro Autistico, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Helen Brittain
- Department of Clinical Genetics, Birmingham Women's & Children's NHS Trust, Birmingham, UK
| | - Traficante Giovanna
- Medical Genetics Unit, Meyer Children's Hospital IRCCS Florence, Florence, Italy
| | - Gori Giulia
- Medical Genetics Unit,Meyer Children's Hospital IRCCS, Florence, Italy
| | - Lina Quteineh
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland
| | - Russia Ha-Vinh Leuchter
- Division of Development and Growth, Department of Pediatrics, University of Geneva, Geneva, Switzerland
| | - Evelien Zonneveld-Huijssoon
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Cecilia Mellado
- Sección de Genética y Errores Congénitos Del Metabolismo, División de Pediatría, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | | | - Mariana Inés Aracena Alvarez
- Unit of Genetics and Metabolic Diseases, Division of Pediatrics, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Milou G P Kennis
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Arianne Bouman
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Maian Roifman
- The Prenatal Diagnosis and Medical Genetics Program, Division of Maternal Fetal Medicine, Department of Obstetrics and Gynaecology, University of Toronto, Toronto, Canada
| | | | - Juan Dario Ortigoza-Escobar
- Movement Disorders Unit, Institut de Recerca Sant Joan de Déu, CIBERER-ISCIII and European Reference Network for Rare Neurological Diseases (ERN-RND), Barcelona, Spain
| | - Vivian Vernimmen
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, the Netherlands; GROW-School for Oncology and Reproduction, Maastricht, the Netherlands
| | - Margje Sinnema
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Rolph Pfundt
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Han G Brunner
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands; Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Lisenka E L M Vissers
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands; Research Institute for Medical Innovation, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Tjitske Kleefstra
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands; Department of Clinical Genetics, Erasmus MC, Rotterdam, the Netherlands; Center of Excellence for Neuropsychiatry, Vincent van Gogh Institute for Psychiatry, Venray, the Netherlands.
| | - Rosanna Weksberg
- Genetics and Genome Biology Program, Research Institute, the Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; Division of Clinical and Metabolic Genetics, Department of Pediatrics, the Hospital for Sick Children, University of Toronto, Toronto, ON M5G 1X8, Canada.
| | - Siddharth Banka
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester, Manchester, UK; Manchester Centre for Genomic Medicine, Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| |
Collapse
|
2
|
Burk KC, Kaneko M, Quindipan C, Vu MH, Cepin MF, Santoro JD, Van Hirtum-Das M, Holder D, Raca G. Diagnostic Yield of Epilepsy-Genes Sequencing and Chromosomal Microarray in Pediatric Epilepsy. Pediatr Neurol 2024; 150:50-56. [PMID: 37979304 DOI: 10.1016/j.pediatrneurol.2023.10.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 09/26/2023] [Accepted: 10/19/2023] [Indexed: 11/20/2023]
Abstract
BACKGROUND Around 40% of individuals with epilepsy have an underlying identifiable genetic etiology. Common methods for epilepsy genetic testing are chromosomal microarray (CMA) and epilepsy-genes sequencing (EGS). Historically, CMA was the first-line test for patients with epilepsy, but recent studies have shown that EGS has a superior diagnostic yield. To further optimize testing algorithms for epilepsy, we compared these tests' diagnostic yields and explored how they are influenced by age of onset and phenotype complexity. METHODS Genetic test results from a cohort of patients with epilepsy were used to determine the diagnostic yield of CMA (n = 366) versus EGS (n = 370) for genetic epilepsy etiologies. Further analysis examined the probability of diagnostic results based on age of seizure onset and patients' phenotype complexity. RESULTS For patients who underwent CMA, causative variants were found in 28 of 366 cases (7.7%), and 60 of 366 patients (16.4%) had at least one variant of uncertain significance (VUS). For EGS, 65 of 370 (17.6%) cases had causative variants, whereas 155 of 370 (41.9%) had at least one VUS. EGS had a significantly higher diagnostic yield than CMA (odds ratio [OR] = 2.63, P < 0.001). This difference in diagnostic yield was further pronounced among patients with infantile seizure onset (OR = 4.69, P < 0.001) and patients with additional neurological findings (OR = 2.99, P < 0.001). CONCLUSION To minimize the time and resources required to reach a diagnosis, clinicians and insurers alike should consider using EGS as an initial diagnostic tool.
Collapse
Affiliation(s)
- Kelly C Burk
- Department of Neurology, Keck School of Medicine of the University of Southern California, Los Angeles, California
| | - Maki Kaneko
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles, Center for Personalized Medicine, Los Angeles, California
| | - Catherine Quindipan
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles, Center for Personalized Medicine, Los Angeles, California
| | - My H Vu
- Biostatistics Core, The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California
| | - Maritza Feliz Cepin
- Division of Neurology, Department of Pediatrics, Children's Hospital Los Angeles, Los Angeles
| | - Jonathan D Santoro
- Department of Neurology, Keck School of Medicine of the University of Southern California, Los Angeles, California; Division of Neurology, Department of Pediatrics, Children's Hospital Los Angeles, Los Angeles
| | - Michele Van Hirtum-Das
- Department of Neurology, Keck School of Medicine of the University of Southern California, Los Angeles, California; Division of Neurology, Department of Pediatrics, Children's Hospital Los Angeles, Los Angeles
| | - Deborah Holder
- Department of Neurology, Keck School of Medicine of the University of Southern California, Los Angeles, California; Division of Neurology, Department of Pediatrics, Children's Hospital Los Angeles, Los Angeles
| | - Gordana Raca
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles, Center for Personalized Medicine, Los Angeles, California.
| |
Collapse
|
3
|
Alsentzer E, Finlayson SG, Li MM, Kobren SN, Kohane IS. Simulation of undiagnosed patients with novel genetic conditions. Nat Commun 2023; 14:6403. [PMID: 37828001 PMCID: PMC10570269 DOI: 10.1038/s41467-023-41980-6] [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: 09/02/2022] [Accepted: 09/26/2023] [Indexed: 10/14/2023] Open
Abstract
Rare Mendelian disorders pose a major diagnostic challenge and collectively affect 300-400 million patients worldwide. Many automated tools aim to uncover causal genes in patients with suspected genetic disorders, but evaluation of these tools is limited due to the lack of comprehensive benchmark datasets that include previously unpublished conditions. Here, we present a computational pipeline that simulates realistic clinical datasets to address this deficit. Our framework jointly simulates complex phenotypes and challenging candidate genes and produces patients with novel genetic conditions. We demonstrate the similarity of our simulated patients to real patients from the Undiagnosed Diseases Network and evaluate common gene prioritization methods on the simulated cohort. These prioritization methods recover known gene-disease associations but perform poorly on diagnosing patients with novel genetic disorders. Our publicly-available dataset and codebase can be utilized by medical genetics researchers to evaluate, compare, and improve tools that aid in the diagnostic process.
Collapse
Grants
- U01 HG007690 NHGRI NIH HHS
- U54 NS108251 NINDS NIH HHS
- U01 HG010219 NHGRI NIH HHS
- U01 HG007672 NHGRI NIH HHS
- U01 HG010233 NHGRI NIH HHS
- U01 HG010230 NHGRI NIH HHS
- U01 HG007943 NHGRI NIH HHS
- U01 HG010217 NHGRI NIH HHS
- U01 HG007942 NHGRI NIH HHS
- U01 HG010215 NHGRI NIH HHS
- U01 HG007708 NHGRI NIH HHS
- T32 HG002295 NHGRI NIH HHS
- T32 GM007753 NIGMS NIH HHS
- U01 HG007674 NHGRI NIH HHS
- U01 TR001395 NCATS NIH HHS
- U01 HG007709 NHGRI NIH HHS
- U54 NS093793 NINDS NIH HHS
- U01 HG007530 NHGRI NIH HHS
- U01 TR002471 NCATS NIH HHS
- U01 HG007703 NHGRI NIH HHS
- UDN research reported in this manuscript was supported by the NIH Common Fund, through the Office of Strategic Coordination/Office of the NIH Director under Award Number(s) U01HG007709, U01HG010219, U01HG010230, U01HG010217, U01HG010233, U01HG010215, U01HG007672, U01HG007690, U01HG007708, U01HG007703, U01HG007674, U01HG007530, U01HG007942, U01HG007943, U01TR001395, U01TR002471, U54NS108251, and U54NS093793.
- E.A. is supported by a Microsoft Research PhD Fellowship.
- S.F. is supported by award Number T32GM007753 from the National Institute of General Medical Sciences.
- M.L. is supported by T32HG002295 from the National Human Genome Research Institute and a National Science Foundation Graduate Research Fellowship.
Collapse
Affiliation(s)
- Emily Alsentzer
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA
- Program in Health Sciences and Technology, MIT, Cambridge, MA, 02139, USA
| | - Samuel G Finlayson
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA
- Program in Health Sciences and Technology, MIT, Cambridge, MA, 02139, USA
- Department of Pediatrics, Division of Genetic Medicine, Seattle Children's Hospital, Seattle, WA, 98105, USA
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA, 98105, USA
| | - Michelle M Li
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA
- Bioinformatics and Integrative Genomics, Harvard Medical School, Boston, MA, 02115, USA
| | - Shilpa N Kobren
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA.
| | - Isaac S Kohane
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA.
| |
Collapse
|
4
|
Clatot J, Parthasarathy S, Cohen S, McKee J, Massey S, Somarowthu A, Goldberg EM, Helbig I. SCN1A gain-of-function mutation causing an early onset epileptic encephalopathy. Epilepsia 2023; 64:1318-1330. [PMID: 36287100 PMCID: PMC10130239 DOI: 10.1111/epi.17444] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 10/21/2022] [Accepted: 10/21/2022] [Indexed: 01/19/2023]
Abstract
OBJECTIVE Loss-of-function variants in SCN1A cause Dravet syndrome, the most common genetic developmental and epileptic encephalopathy (DEE). However, emerging evidence suggests separate entities of SCN1A-related disorders due to gain-of-function variants. Here, we aim to refine the clinical, genetic, and functional electrophysiological features of a recurrent p.R1636Q gain-of-function variant, identified in four individuals at a single center. METHODS Individuals carrying the recurrent SCN1A p.R1636Q variant were identified through diagnostic testing. Whole cell voltage-clamp electrophysiological recording in HEK-293 T cells was performed to compare the properties of sodium channels containing wild-type Nav 1.1 or Nav 1.1-R1636Q along with both Nav β1 and Nav β2 subunits, including response to oxcarbazepine. To delineate differences from other SCN1A-related epilepsies, we analyzed electronic medical records. RESULTS All four individuals had an early onset DEE characterized by focal tonic seizures and additional seizure types starting in the first few weeks of life. Electrophysiological analysis showed a mixed gain-of-function effect with normal current density, a leftward (hyperpolarized) shift of steady-state inactivation, and slower inactivation kinetics leading to a prominent late sodium current. The observed functional changes closely paralleled effects of pathogenic variants in SCN3A and SCN8A at corresponding positions. Both wild type and variant exhibited sensitivity to block by oxcarbazepine, partially correcting electrophysiological abnormalities of the SCN1A p.R1636Q variant. Clinically, a single individual responded to treatment with oxcarbazepine. Across 51 individuals with SCN1A-related epilepsies, those with the recurrent p.R1636Q variants had the earliest ages at onset. SIGNIFICANCE The recurrent SCN1A p.R1636Q variant causes a clinical entity with a wider clinical spectrum than previously reported, characterized by neonatal onset epilepsy and absence of prominent movement disorder. Functional consequences of this variant lead to mixed loss and gain of function that is partially corrected by oxcarbazepine. The recurrent p.R1636Q variant represents one of the most common causes of early onset SCN1A-related epilepsies with separate treatment and prognosis implications.
Collapse
Affiliation(s)
- Jérôme Clatot
- Division of Neurology, Department of Pediatrics
- The Epilepsy NeuroGenetics Initiative, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Shridhar Parthasarathy
- Division of Neurology, Department of Pediatrics
- Department of Biomedical Health Informatics (DBHi)
- The Epilepsy NeuroGenetics Initiative, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Stacey Cohen
- Division of Neurology, Department of Pediatrics
- Department of Biomedical Health Informatics (DBHi)
- The Epilepsy NeuroGenetics Initiative, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jillian McKee
- Division of Neurology, Department of Pediatrics
- The Epilepsy NeuroGenetics Initiative, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Shavonne Massey
- Division of Neurology, Department of Pediatrics
- The Epilepsy NeuroGenetics Initiative, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | | | - Ethan M. Goldberg
- Division of Neurology, Department of Pediatrics
- Department of Biomedical Health Informatics (DBHi)
- Department of Neurology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
- Department of Neuroscience, University of Pennsylvania School of Medicine, Philadelphia, USA
| | - Ingo Helbig
- Division of Neurology, Department of Pediatrics
- Department of Biomedical Health Informatics (DBHi)
- The Epilepsy NeuroGenetics Initiative, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Neurology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| |
Collapse
|
5
|
Spagnoli C, Fusco C, Pisani F. Pediatric-Onset Epilepsy and Developmental Epileptic Encephalopathies Followed by Early-Onset Parkinsonism. Int J Mol Sci 2023; 24:ijms24043796. [PMID: 36835207 PMCID: PMC9965035 DOI: 10.3390/ijms24043796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 02/09/2023] [Accepted: 02/10/2023] [Indexed: 02/16/2023] Open
Abstract
Genetic early-onset Parkinsonism is unique due to frequent co-occurrence of hyperkinetic movement disorder(s) (MD), or additional neurological of systemic findings, including epilepsy in up to 10-15% of cases. Based on both the classification of Parkinsonism in children proposed by Leuzzi and coworkers and the 2017 ILAE epilepsies classification, we performed a literature review in PubMed. A few discrete presentations can be identified: Parkinsonism as a late manifestation of complex neurodevelopmental disorders, characterized by developmental and epileptic encephalopathies (DE-EE), with multiple, refractory seizure types and severely abnormal EEG characteristics, with or without preceding hyperkinetic MD; Parkinsonism in the context of syndromic conditions with unspecific reduced seizure threshold in infancy and childhood; neurodegenerative conditions with brain iron accumulation, in which childhood DE-EE is followed by neurodegeneration; and finally, monogenic juvenile Parkinsonism, in which a subset of patients with intellectual disability or developmental delay (ID/DD) develop hypokinetic MD between 10 and 30 years of age, following unspecific, usually well-controlled, childhood epilepsy. This emerging group of genetic conditions leading to epilepsy or DE-EE in childhood followed by juvenile Parkinsonism highlights the need for careful long-term follow-up, especially in the context of ID/DD, in order to readily identify individuals at increased risk of later Parkinsonism.
Collapse
Affiliation(s)
- Carlotta Spagnoli
- Child Neurology and Psychiatry Unit, Department of Pediatrics, Presidio Ospedaliero Santa Maria Nuova, AUSL-IRCCS di Reggio Emilia, 42122 Reggio Emilia, Italy
- Correspondence: ; Tel.: +39-0522-296033
| | - Carlo Fusco
- Child Neurology and Psychiatry Unit, Department of Pediatrics, Presidio Ospedaliero Santa Maria Nuova, AUSL-IRCCS di Reggio Emilia, 42122 Reggio Emilia, Italy
| | - Francesco Pisani
- Human Neurosciences Department, Sapienza University of Rome, 00185 Rome, Italy
| |
Collapse
|
6
|
Al Anazi AH, Ammar AS, Al-Hajj M, Cyrus C, Aljaafari D, Khoda I, Abdelfatah AK, Alsulaiman AA, Alanazi F, Alanazi R, Gandla D, Lad H, Barayan S, Keating BJ, Al-Ali AK. Whole-exome sequencing of a Saudi epilepsy cohort reveals association signals in known and potentially novel loci. Hum Genomics 2022; 16:71. [PMID: 36539902 PMCID: PMC9764464 DOI: 10.1186/s40246-022-00444-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Epilepsy, a serious chronic neurological condition effecting up to 100 million people globally, has clear genetic underpinnings including common and rare variants. In Saudi Arabia, the prevalence of epilepsy is high and caused mainly by perinatal and genetic factors. No whole-exome sequencing (WES) studies have been performed to date in Saudi Arabian epilepsy cohorts. This offers a unique opportunity for the discovery of rare genetic variants impacting this disease as there is a high rate of consanguinity among large tribal pedigrees. RESULTS We performed WES on 144 individuals diagnosed with epilepsy, to interrogate known epilepsy-related genes for known and functional novel variants. We also used an American College of Medical Genetics (ACMG) guideline-based variant prioritization approach in an attempt to discover putative causative variants. We identified 32 potentially causative pathogenic variants across 30 different genes in 44/144 (30%) of these Saudi epilepsy individuals. We also identified 232 variants of unknown significance (VUS) across 101 different genes in 133/144 (92%) subjects. Strong enrichment of variants of likely pathogenicity was observed in previously described epilepsy-associated loci, and a number of putative pathogenic variants in novel loci are also observed. CONCLUSION Several putative pathogenic variants in known epilepsy-related loci were identified for the first time in our population, in addition to several potential new loci which may be prioritized for further investigation.
Collapse
Affiliation(s)
- Abdulrahman H. Al Anazi
- grid.411975.f0000 0004 0607 035XDepartment of Neurosurgery, King Fahd Hospital of the University, Alkhobar, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Ahmed S. Ammar
- grid.411975.f0000 0004 0607 035XDepartment of Neurosurgery, King Fahd Hospital of the University, Alkhobar, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Mahmoud Al-Hajj
- grid.415296.d0000 0004 0607 1539Department of Neurosurgery, King Fahd Hospital, Alhafof, Saudi Arabia
| | - Cyril Cyrus
- grid.411975.f0000 0004 0607 035XDepartment of Clinical Biochemistry, College of Medicine, Imam Abdulrahman Bin Faisal University, P. O. Box 1982, 31441 Dammam, Saudi Arabia
| | - Danah Aljaafari
- grid.411975.f0000 0004 0607 035XDepartment of Neurology, King Fahd Hospital of the University, Alkhobar, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Iname Khoda
- grid.411975.f0000 0004 0607 035XDepartment of Neurology, King Fahd Hospital of the University, Alkhobar, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Ahmed K. Abdelfatah
- grid.411975.f0000 0004 0607 035XDepartment of Neurosurgery, King Fahd Hospital of the University, Alkhobar, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Abdullah A. Alsulaiman
- grid.411975.f0000 0004 0607 035XDepartment of Neurology, King Fahd Hospital of the University, Alkhobar, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Firas Alanazi
- grid.411975.f0000 0004 0607 035XDepartment of Neurosurgery, King Fahd Hospital of the University, Alkhobar, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Rawan Alanazi
- grid.411975.f0000 0004 0607 035XDepartment of Neurosurgery, King Fahd Hospital of the University, Alkhobar, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Divya Gandla
- grid.25879.310000 0004 1936 8972Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA USA
| | - Hetal Lad
- grid.25879.310000 0004 1936 8972Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA USA
| | - Samar Barayan
- grid.411975.f0000 0004 0607 035XDepartment of Neurosurgery, King Fahd Hospital of the University, Alkhobar, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Brendan J. Keating
- grid.25879.310000 0004 1936 8972Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA USA
| | - Amein K. Al-Ali
- grid.411975.f0000 0004 0607 035XDepartment of Clinical Biochemistry, College of Medicine, Imam Abdulrahman Bin Faisal University, P. O. Box 1982, 31441 Dammam, Saudi Arabia
| |
Collapse
|
7
|
Jacobsen JOB, Kelly C, Cipriani V, Research Consortium GE, Mungall CJ, Reese J, Danis D, Robinson PN, Smedley D. Phenotype-driven approaches to enhance variant prioritization and diagnosis of rare disease. Hum Mutat 2022; 43:1071-1081. [PMID: 35391505 PMCID: PMC9288531 DOI: 10.1002/humu.24380] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 01/25/2022] [Accepted: 04/03/2022] [Indexed: 11/20/2022]
Abstract
Rare disease diagnostics and disease gene discovery have been revolutionized by whole-exome and genome sequencing but identifying the causative variant(s) from the millions in each individual remains challenging. The use of deep phenotyping of patients and reference genotype-phenotype knowledge, alongside variant data such as allele frequency, segregation, and predicted pathogenicity, has proved an effective strategy to tackle this issue. Here we review the numerous tools that have been developed to automate this approach and demonstrate the power of such an approach on several thousand diagnosed cases from the 100,000 Genomes Project. Finally, we discuss the challenges that need to be overcome if we are going to improve detection rates and help the majority of patients that still remain without a molecular diagnosis after state-of-the-art genomic interpretation.
Collapse
Affiliation(s)
- Julius O. B. Jacobsen
- William Harvey Research Institute, Charterhouse Square, Barts and the London School of Medicine and Dentistry QueenQueen Mary University of LondonLondonUK
| | - Catherine Kelly
- William Harvey Research Institute, Charterhouse Square, Barts and the London School of Medicine and Dentistry QueenQueen Mary University of LondonLondonUK
| | - Valentina Cipriani
- William Harvey Research Institute, Charterhouse Square, Barts and the London School of Medicine and Dentistry QueenQueen Mary University of LondonLondonUK
| | | | - Christopher J. Mungall
- Environmental Genomics and Systems Biology, Lawrence Berkeley National LaboratoryBerkeleyCaliforniaUSA
| | - Justin Reese
- Environmental Genomics and Systems Biology, Lawrence Berkeley National LaboratoryBerkeleyCaliforniaUSA
| | - Daniel Danis
- The Jackson Laboratory for Genomic MedicineFarmingtonConnecticutUSA
| | | | - Damian Smedley
- William Harvey Research Institute, Charterhouse Square, Barts and the London School of Medicine and Dentistry QueenQueen Mary University of LondonLondonUK
| |
Collapse
|
8
|
A novel missense variant in the LMNB2 gene causes progressive myoclonus epilepsy. Acta Neurol Belg 2022; 122:659-667. [PMID: 33783721 DOI: 10.1007/s13760-021-01650-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 03/08/2021] [Indexed: 12/18/2022]
Abstract
Progressive myoclonus epilepsies (PMEs) are a group of disorders embracing myoclonus, seizures, and neurological dysfunctions. Because of the genetic and clinical heterogeneity, a large proportion of PMEs cases have remained molecularly undiagnosed. The present study aimed to determine the underlying genetic factors that contribute to the PME phenotype in an Iranian female patient. We describe a consanguineous Iranian family with autosomal recessive PME that had remained undiagnosed despite extensive genetic and pathological tests. After performing neuroimaging and clinical examinations, due to heterogeneity of PMEs, the proband was subjected to paired-end whole-exome sequencing and the candidate variant was confirmed by Sanger sequencing. Various in-silico tools were also used to predict the pathogenicity of the variant. In this study, we identified a novel homozygous missense variant (NM_032737.4:c.472C > T; p.(Arg158Trp)) in the LMNB2 gene (OMIM: 150341) as the most likely disease-causing variant. Neuroimaging revealed a progressive significant generalized atrophy in the cerebral and cerebellum without significant white matter signal changes. Video-electroencephalography monitoring showed a generalized pattern of high-voltage sharp waves in addition to multifocal spikes and waves compatible with mixed type seizures and epileptic encephalopathic pattern. Herein, we introduce the second case of PME caused by a novel variant in the LMNB2 gene. This study also underscores the potentiality of next-generation sequencing in the genetic diagnosis of patients with neurologic diseases with an unknown cause.
Collapse
|
9
|
Cloney T, Gallacher L, Pais LS, Tan NB, Yeung A, Stark Z, Brown NJ, McGillivray G, Delatycki MB, de Silva MG, Downie L, Stutterd CA, Elliott J, Compton AG, Lovgren A, Oertel R, Francis D, Bell KM, Sadedin S, Lim SC, Helman G, Simons C, Macarthur DG, Thorburn DR, O'Donnell-Luria AH, Christodoulou J, White SM, Tan TY. Lessons learnt from multifaceted diagnostic approaches to the first 150 families in Victoria's Undiagnosed Diseases Program. J Med Genet 2021; 59:748-758. [PMID: 34740920 DOI: 10.1136/jmedgenet-2021-107902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Accepted: 09/14/2021] [Indexed: 01/18/2023]
Abstract
BACKGROUND Clinical exome sequencing typically achieves diagnostic yields of 30%-57.5% in individuals with monogenic rare diseases. Undiagnosed diseases programmes implement strategies to improve diagnostic outcomes for these individuals. AIM We share the lessons learnt from the first 3 years of the Undiagnosed Diseases Program-Victoria, an Australian programme embedded within a clinical genetics service in the state of Victoria with a focus on paediatric rare diseases. METHODS We enrolled families who remained without a diagnosis after clinical genomic (panel, exome or genome) sequencing between 2016 and 2018. We used family-based exome sequencing (family ES), family-based genome sequencing (family GS), RNA sequencing (RNA-seq) and high-resolution chromosomal microarray (CMA) with research-based analysis. RESULTS In 150 families, we achieved a diagnosis or strong candidate in 64 (42.7%) (37 in known genes with a consistent phenotype, 3 in known genes with a novel phenotype and 24 in novel disease genes). Fifty-four diagnoses or strong candidates were made by family ES, six by family GS with RNA-seq, two by high-resolution CMA and two by data reanalysis. CONCLUSION We share our lessons learnt from the programme. Flexible implementation of multiple strategies allowed for scalability and response to the availability of new technologies. Broad implementation of family ES with research-based analysis showed promising yields post a negative clinical singleton ES. RNA-seq offered multiple benefits in family ES-negative populations. International data sharing strategies were critical in facilitating collaborations to establish novel disease-gene associations. Finally, the integrated approach of a multiskilled, multidisciplinary team was fundamental to having diverse perspectives and strategic decision-making.
Collapse
Affiliation(s)
- Thomas Cloney
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Lyndon Gallacher
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Lynn S Pais
- Center for Mendelian Genomics, Eli and Edythe L Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA.,Division of Genetics and Genomics, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Natalie B Tan
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Alison Yeung
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Zornitza Stark
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Natasha J Brown
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - George McGillivray
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Martin B Delatycki
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Michelle G de Silva
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Lilian Downie
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Chloe A Stutterd
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Justine Elliott
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Alison G Compton
- Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia.,Brain and Mitochondrial Research Group, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Alysia Lovgren
- Center for Mendelian Genomics, Eli and Edythe L Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA.,Analytic and Translational Genomics Unit, Massachusetts General Hospital, Boston, Massachusetts, USA.,Program in Medical and Population Genetics, Broad Institute, Cambridge, Massachusetts, USA
| | - Ralph Oertel
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - David Francis
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Katrina M Bell
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Bioinformatics, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Simon Sadedin
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Sze Chern Lim
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Guy Helman
- Brain and Mitochondrial Research Group, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Cas Simons
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Translational Bioinformatics, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Daniel G Macarthur
- Center for Mendelian Genomics, Eli and Edythe L Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA.,Centre for Population Genomics, Garvan Institute of Medical Research, Sydney, New South Wales, Australia.,Centre for Population Genomics, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - David R Thorburn
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia.,Brain and Mitochondrial Research Group, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Anne H O'Donnell-Luria
- Center for Mendelian Genomics, Eli and Edythe L Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA.,Division of Genetics and Genomics, Boston Children's Hospital, Boston, Massachusetts, USA.,Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - John Christodoulou
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia.,Neurodevelopmental Genomics Research Group, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Susan M White
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Tiong Yang Tan
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Victoria, Australia .,Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| |
Collapse
|
10
|
Next-generation sequencing in childhood-onset epilepsies: Diagnostic yield and impact on neuronal ceroid lipofuscinosis type 2 (CLN2) disease diagnosis. PLoS One 2021; 16:e0255933. [PMID: 34469436 PMCID: PMC8409681 DOI: 10.1371/journal.pone.0255933] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 07/27/2021] [Indexed: 11/19/2022] Open
Abstract
Epilepsy is one of the most common childhood-onset neurological conditions with a genetic etiology. Genetic diagnosis provides potential for etiologically-based management and treatment. Existing research has focused on early-onset (<24 months) epilepsies; data regarding later-onset epilepsies is limited. The goal of this study was to determine the diagnostic yield of a clinically available epilepsy panel in a selected pediatric epilepsy cohort with epilepsy onset between 24-60 months of life and evaluate whether this approach decreases the age of diagnosis of neuronal ceroid lipofuscinosis type 2 (CLN2). Next-generation sequencing (NGS)-based epilepsy panels, including genes associated with epileptic encephalopathies and inborn errors of metabolism (IEMs) that present with epilepsy, were used. Copy-number variant (CNV) detection from NGS data was included. Variant interpretation was performed per American College of Medical Genetics and Genomics (ACMG) guidelines. Results are reported from 211 consecutive patients with the following inclusion criteria: 24-60 months of age at the time of enrollment, first unprovoked seizure at/after 24 months, and at least one additional finding such as EEG/MRI abnormalities, speech delay, or motor symptoms. Median age was 42 months at testing and 30 months at first seizure onset; the mean delay from first seizure to comprehensive genetic testing was 10.3 months. A genetic diagnosis was established in 43 patients (20.4%). CNVs were reported in 25.6% diagnosed patients; 27.3% of CNVs identified were intragenic. Within the diagnosed cohort, 11 (25.6%) patients were diagnosed with an IEM. The predominant molecular diagnosis was CLN2 (14% of diagnosed patients). For these patients, diagnosis was achieved 12-24 months earlier than reported by natural history of the disease. This study supports comprehensive genetic testing for patients whose first seizure occurs ≥ 24 months of age. It also supports early application of testing in this age group, as the identified diagnoses can have significant impact on patient management and outcome.
Collapse
|
11
|
Jiang T, Gao J, Jiang L, Xu L, Zhao C, Su X, Shen Y, Gu W, Kong X, Yang Y, Gao F. Application of Trio-Whole Exome Sequencing in Genetic Diagnosis and Therapy in Chinese Children With Epilepsy. Front Mol Neurosci 2021; 14:699574. [PMID: 34489640 PMCID: PMC8417468 DOI: 10.3389/fnmol.2021.699574] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 07/30/2021] [Indexed: 11/13/2022] Open
Abstract
Epilepsy is one of the most common neurological disorders in pediatric patients with other underlying neurological defects. Identifying the underlying etiology is crucial for better management of the disorder. We performed trio-whole exome sequencing in 221 pediatric patients with epilepsy. Probands were divided into seizures with developmental delay/intellectual disability (DD/ID) and seizures without DD/ID groups. Pathogenic (P) or likely pathogenic (LP) variants were identified in 71/110 (64.5%) patients in the seizures with DD/ID group and 21/111 (18.9%) patients in the seizures without DD/ID group (P < 0.001). Eighty-seven distinct P/LP single nucleotide variants (SNVs)/insertion deletions (Indels) were detected, with 55.2% (48/87) of them being novel. All aneuploidy and P/LP copy number variants (CNVs) larger than 100 Kb were identifiable by both whole-exome sequencing and copy number variation sequencing (CNVseq) in 123 of individuals (41 pedigrees). Ten of P/LP CNVs in nine patients and one aneuploidy variant in one patient (Patient #56, #47, XXY) were identified by CNVseq. Herein, we identified seven genes (NCL, SEPHS2, PA2G4, SLC35G2, MYO1C, GPR158, and POU3F1) with de novo variants but unknown pathogenicity that were not previously associated with epilepsy. Potential effective treatment options were available for 32 patients with a P/LP variant, based on the molecular diagnosis. Genetic testing may help identify the molecular etiology of early onset epilepsy and DD/ID and further aid to choose the appropriate treatment strategy for patients.
Collapse
Affiliation(s)
- Tiejia Jiang
- Department of Neurology, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Jia Gao
- Department of Neurology, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Lihua Jiang
- Department of Neurology, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Lu Xu
- Department of Neurology, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Congying Zhao
- Department of Neurology, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Xiaojun Su
- Department of Neurology, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Yaping Shen
- Department of Neurology, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Weiyue Gu
- Beijing Chigene Translational Medical Research Center Co., Ltd., Beijing, China
| | - Xiaohong Kong
- Beijing Chigene Translational Medical Research Center Co., Ltd., Beijing, China
| | - Ying Yang
- Beijing Chigene Translational Medical Research Center Co., Ltd., Beijing, China
| | - Feng Gao
- Department of Neurology, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| |
Collapse
|
12
|
New avenues in molecular genetics for the diagnosis and application of therapeutics to the epilepsies. Epilepsy Behav 2021; 121:106428. [PMID: 31400936 DOI: 10.1016/j.yebeh.2019.07.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 06/14/2019] [Accepted: 07/06/2019] [Indexed: 11/22/2022]
Abstract
Genetic epidemiology studies have shown that most epilepsies involve some genetic cause. In addition, twin studies have helped strengthen the hypothesis that in most patients with epilepsy, a complex inheritance is involved. More recently, with the development of high-density single-nucleotide polymorphism (SNP) microarrays and next-generation sequencing (NGS) technologies, the discovery of genes related to the epilepsies has accelerated tremendously. Especially, the use of whole exome sequencing (WES) has had a considerable impact on the identification of rare genetic variants with large effect sizes, including inherited or de novo mutations in severe forms of childhood epilepsies. The identification of pathogenic variants in patients with these childhood epilepsies provides many benefits for patients and families, such as the confirmation of the genetic nature of the diseases. This process will allow for better genetic counseling, more accurate therapy decisions, and a significant positive emotional impact. However, to study the genetic component of the more common forms of epilepsy, the use of high-density SNP arrays in genome-wide association studies (GWAS) seems to be the strategy of choice. As such, researchers can identify loci containing genetic variants associated with the common forms of epilepsy. The knowledge generated over the past two decades about the effects of the mutations that cause the monogenic epilepsy is tremendous; however, the scientific community is just starting to apply this information in order to generate better target treatments.
Collapse
|
13
|
Menezes LFS, Sabiá Júnior EF, Tibery DV, Carneiro LDA, Schwartz EF. Epilepsy-Related Voltage-Gated Sodium Channelopathies: A Review. Front Pharmacol 2020; 11:1276. [PMID: 33013363 PMCID: PMC7461817 DOI: 10.3389/fphar.2020.01276] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 07/31/2020] [Indexed: 12/29/2022] Open
Abstract
Epilepsy is a disease characterized by abnormal brain activity and a predisposition to generate epileptic seizures, leading to neurobiological, cognitive, psychological, social, and economic impacts for the patient. There are several known causes for epilepsy; one of them is the malfunction of ion channels, resulting from mutations. Voltage-gated sodium channels (NaV) play an essential role in the generation and propagation of action potential, and malfunction caused by mutations can induce irregular neuronal activity. That said, several genetic variations in NaV channels have been described and associated with epilepsy. These mutations can affect channel kinetics, modifying channel activation, inactivation, recovery from inactivation, and/or the current window. Among the NaV subtypes related to epilepsy, NaV1.1 is doubtless the most relevant, with more than 1500 mutations described. Truncation and missense mutations are the most observed alterations. In addition, several studies have already related mutated NaV channels with the electrophysiological functioning of the channel, aiming to correlate with the epilepsy phenotype. The present review provides an overview of studies on epilepsy-associated mutated human NaV1.1, NaV1.2, NaV1.3, NaV1.6, and NaV1.7.
Collapse
Affiliation(s)
- Luis Felipe Santos Menezes
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
| | - Elias Ferreira Sabiá Júnior
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
| | - Diogo Vieira Tibery
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
| | - Lilian Dos Anjos Carneiro
- Faculdade de Medicina, Centro Universitário Euro Americano, Brasília, Brazil.,Faculdade de Medicina, Centro Universitário do Planalto Central, Brasília, Brazil
| | - Elisabeth Ferroni Schwartz
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
| |
Collapse
|
14
|
Rochtus A, Olson HE, Smith L, Keith LG, El Achkar C, Taylor A, Mahida S, Park M, Kelly M, Shain C, Rockowitz S, Sheidley BR, Poduri A. Genetic diagnoses in epilepsy: The impact of dynamic exome analysis in a pediatric cohort. Epilepsia 2020; 61:249-258. [PMID: 31957018 PMCID: PMC7404709 DOI: 10.1111/epi.16427] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 12/18/2019] [Accepted: 12/20/2019] [Indexed: 01/02/2023]
Abstract
OBJECTIVE We evaluated the yield of systematic analysis and/or reanalysis of whole exome sequencing (WES) data from a cohort of well-phenotyped pediatric patients with epilepsy and suspected but previously undetermined genetic etiology. METHODS We identified and phenotyped 125 participants with pediatric epilepsy. Etiology was unexplained at the time of enrollment despite clinical testing, which included chromosomal microarray (57 patients), epilepsy gene panel (n = 48), both (n = 28), or WES (n = 8). Clinical epilepsy diagnoses included developmental and epileptic encephalopathy (DEE), febrile infection-related epilepsy syndrome, Rasmussen encephalitis, and other focal and generalized epilepsies. We analyzed WES data and compared the yield in participants with and without prior clinical genetic testing. RESULTS Overall, we identified pathogenic or likely pathogenic variants in 40% (50/125) of our study participants. Nine patients with DEE had genetic variants in recently published genes that had not been recognized as epilepsy-related at the time of clinical testing (FGF12, GABBR1, GABBR2, ITPA, KAT6A, PTPN23, RHOBTB2, SATB2), and eight patients had genetic variants in candidate epilepsy genes (CAMTA1, FAT3, GABRA6, HUWE1, PTCHD1). Ninety participants had concomitant or subsequent clinical genetic testing, which was ultimately explanatory for 26% (23/90). Of the 67 participants whose molecular diagnoses were "unsolved" through clinical genetic testing, we identified pathogenic or likely pathogenic variants in 17 (25%). SIGNIFICANCE Our data argue for early consideration of WES with iterative reanalysis for patients with epilepsy, particularly those with DEE or epilepsy with intellectual disability. Rigorous analysis of WES data of well-phenotyped patients with epilepsy leads to a broader understanding of gene-specific phenotypic spectra as well as candidate disease gene identification. We illustrate the dynamic nature of genetic diagnosis over time, with analysis and in some cases reanalysis of exome data leading to the identification of disease-associated variants among participants with previously nondiagnostic results from a variety of clinical testing strategies.
Collapse
Affiliation(s)
- Anne Rochtus
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
- Department of Pediatrics, University of Leuven, Leuven, Belgium
| | - Heather E. Olson
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Lacey Smith
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
| | - Louisa G. Keith
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
| | - Christelle El Achkar
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Alan Taylor
- Department of Genomics, Al Jalila Children’s Specialty Hospital, Dubai, UAE
| | - Sonal Mahida
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
| | - Meredith Park
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
| | - McKenna Kelly
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
| | - Catherine Shain
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
| | - Shira Rockowitz
- Information Services Department, Boston Children’s Hospital, Boston, MA, USA
| | - Beth Rosen Sheidley
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
| | - Annapurna Poduri
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
15
|
Li X, Xie LL, Han W, Hong SQ, Ma JN, Wang J, Jiang L. Clinical Forms and GRIN2A Genotype of Severe End of Epileptic-Aphasia Spectrum Disorder. Front Pediatr 2020; 8:574803. [PMID: 33240831 PMCID: PMC7677254 DOI: 10.3389/fped.2020.574803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Accepted: 09/28/2020] [Indexed: 11/25/2022] Open
Abstract
Objective: This study aims to analyze the electroclinical characteristics and gene test results of children on the severe end of the epilepsy aphasia spectrum (EAS) and also the correlation of EAS-related GRIN2A genes to explore the genotype-phenotype relationships, as well as potential pathogenic mechanism of EAS. Methods: A retrospective study was conducted on the participants diagnosed with Landau-Kleffner syndrome (LKS), epileptic encephalopathy with continuous spike-and-wave during sleep (CSWS), and atypical benign partial epilepsy (ABPE) at the Children's Hospital of Chongqing Medical University from January 2013 to June 2019. Whole-exome sequencing was performed in six patients, and epileptic panel was carried out in two. In addition, we reviewed all the published literatures reporting EAS patients with pathogenic variants until June 2019 and conducted Gene Ontology (GO) analysis, as well as protein-protein interaction (PPI) network. Results: The mean age at seizure onset was 55.4 ± 27.0 months. The baseline severity of the spike-wave index (SWI) was not significantly correlated with intellectual disability (ID) level. Two pathogenic de novo GRIN2A null variants were identified in patients with ABPE who had less severe ID, despite the electrical status epilepticus during slow-wave sleep (ESES). By literature reviewing, 18 GRIN2A missense mutations and 11 GRIN2A truncating mutations which lead to N-methyl-d-aspartate receptors' loss of function has been reported. Of these mutations, 9 (31.0%) are situated in amino (N)-terminal domain, 6 (20.7%) in linger-binding domain S1, and 10 (34.5%) in linger-binding domain S2. EAS-related genes were enriched in the biological process of chemical synaptic transmission and vocalization (FDR, <0.01). The hub protein in PPI network is GluN2A, which might affect language function via foxp2-srpx2/uPAR signal network. Conclusion: Our data suggested that when children suspected with benign epilepsy of children with centrotemporal spikes (BECTs) have early-onset age, changed seizure semiology, and deterioration of behavior/cognition/motor function, neurologists should be alert of the appearance of ESES. The neuropsychological deterioration in children with EAS might not only be completely affected by electric discharge severity but also genetic etiology. Our finding also enforced the current genotype-phenotype relationship theory about EAS. For EAS children, GRIN2A-FOXP2-SRPX2/uPAR signal network might contribute to the mechanism of their language deficit.
Collapse
Affiliation(s)
- Xiao Li
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Chongqing, China.,China International Science and Technology Cooperation base of Child Development and Critical Disorders, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Ling-Ling Xie
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Chongqing, China.,China International Science and Technology Cooperation base of Child Development and Critical Disorders, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Wei Han
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Chongqing, China.,China International Science and Technology Cooperation base of Child Development and Critical Disorders, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Si-Qi Hong
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Chongqing, China.,China International Science and Technology Cooperation base of Child Development and Critical Disorders, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Jian-Nan Ma
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Chongqing, China.,China International Science and Technology Cooperation base of Child Development and Critical Disorders, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Juan Wang
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Chongqing, China.,China International Science and Technology Cooperation base of Child Development and Critical Disorders, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Li Jiang
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Chongqing, China.,China International Science and Technology Cooperation base of Child Development and Critical Disorders, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Chongqing, China
| |
Collapse
|
16
|
What is the role of next generation sequencing in status epilepticus? Epilepsy Behav 2019; 101:106373. [PMID: 31300382 DOI: 10.1016/j.yebeh.2019.06.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 06/11/2019] [Indexed: 02/01/2023]
Abstract
Status epilepticus is a life-threatening medical condition which requires immediate diagnosis and treatment. In children, it may be a recurrent manifestation in the context of heterogeneous severe developmental genetic encephalopathies, as well as the first neurological manifestation. Mutations in several genes have been consistently associated with status epilepticus despite none of them can be considered as 'pure' Mendelian status epilepticus gene. Most genetic conditions featuring status epilepticus can be assigned to specific phenotypic subgroups, including cortical dysplasias, inborn errors of metabolism, mitochondrial diseases, or epileptic encephalopathies and childhood syndromes. Next generation sequencing (NGS) has increased the number of genes associated with, and improved the turnaround time for molecular diagnosis of, status epilepticus, allowing more timely and rationale management choices for specific conditions. Next generation sequencing might become part of the standard of care in the near future for a large subset of patients with status epilepticus, especially in early life. At present, trios whole exome sequencing, with a first analysis of point and copy number variants of an in silico panel containing 'status epilepticus' genes might represent best choice as it would allow a rapid screening. This article is part of the Special Issue "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures".
Collapse
|
17
|
Myers SJ, Yuan H, Kang JQ, Tan FCK, Traynelis SF, Low CM. Distinct roles of GRIN2A and GRIN2B variants in neurological conditions. F1000Res 2019; 8:F1000 Faculty Rev-1940. [PMID: 31807283 PMCID: PMC6871362 DOI: 10.12688/f1000research.18949.1] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/08/2019] [Indexed: 12/12/2022] Open
Abstract
Rapid advances in sequencing technology have led to an explosive increase in the number of genetic variants identified in patients with neurological disease and have also enabled the assembly of a robust database of variants in healthy individuals. A surprising number of variants in the GRIN genes that encode N-methyl-D-aspartate (NMDA) glutamatergic receptor subunits have been found in patients with various neuropsychiatric disorders, including autism spectrum disorders, epilepsy, intellectual disability, attention-deficit/hyperactivity disorder, and schizophrenia. This review compares and contrasts the available information describing the clinical and functional consequences of genetic variations in GRIN2A and GRIN2B. Comparison of clinical phenotypes shows that GRIN2A variants are commonly associated with an epileptic phenotype but that GRIN2B variants are commonly found in patients with neurodevelopmental disorders. These observations emphasize the distinct roles that the gene products serve in circuit function and suggest that functional analysis of GRIN2A and GRIN2B variation may provide insight into the molecular mechanisms, which will allow more accurate subclassification of clinical phenotypes. Furthermore, characterization of the pharmacological properties of variant receptors could provide the first opportunity for translational therapeutic strategies for these GRIN-related neurological and psychiatric disorders.
Collapse
Affiliation(s)
- Scott J Myers
- Center for Functional Evaluation of Rare Variants (CFERV), Emory University, Atlanta, GA, USA
- Department of Pharmacology and Chemical Biology, Emory University, Atlanta, GA, USA
| | - Hongjie Yuan
- Center for Functional Evaluation of Rare Variants (CFERV), Emory University, Atlanta, GA, USA
- Department of Pharmacology and Chemical Biology, Emory University, Atlanta, GA, USA
| | - Jing-Qiong Kang
- Department of Neurology, Vanderbilt Brain Institute, Vanderbilt Kennedy Center of Human Development, Vanderbilt University, Nashville, TN, USA
| | - Francis Chee Kuan Tan
- Department of Anaesthesia, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Stephen F Traynelis
- Center for Functional Evaluation of Rare Variants (CFERV), Emory University, Atlanta, GA, USA
- Department of Pharmacology and Chemical Biology, Emory University, Atlanta, GA, USA
| | - Chian-Ming Low
- Department of Anaesthesia, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| |
Collapse
|
18
|
Pope S, Artuch R, Heales S, Rahman S. Cerebral folate deficiency: Analytical tests and differential diagnosis. J Inherit Metab Dis 2019; 42:655-672. [PMID: 30916789 DOI: 10.1002/jimd.12092] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 03/19/2019] [Accepted: 03/25/2019] [Indexed: 11/07/2022]
Abstract
Cerebral folate deficiency is typically defined as a deficiency of the major folate species 5-methyltetrahydrofolate in the cerebrospinal fluid (CSF) in the presence of normal peripheral total folate levels. However, it should be noted that cerebral folate deficiency is also often used to describe conditions where CSF 5-MTHF is low, in the presence of low or undefined peripheral folate levels. Known defects of folate transport are deficiency of the proton coupled folate transporter, associated with systemic as well as cerebral folate deficiency, and deficiency of the folate receptor alpha, leading to an isolated cerebral folate deficiency associated with intractable seizures, developmental delay and/or regression, progressive ataxia and choreoathetoid movement disorders. Inborn errors of folate metabolism include deficiencies of the enzymes methylenetetrahydrofolate reductase, dihydrofolate reductase and 5,10-methenyltetrahydrofolate synthetase. Cerebral folate deficiency is potentially a treatable condition and so prompt recognition of these inborn errors and initiation of appropriate therapy is of paramount importance. Secondary cerebral folate deficiency may be observed in other inherited metabolic diseases, including disorders of the mitochondrial oxidative phosphorylation system, serine deficiency, and pyridoxine dependent epilepsy. Other secondary causes of cerebral folate deficiency include the effects of drugs, immune response activation, toxic insults and oxidative stress. This review describes the absorption, transport and metabolism of folate within the body; analytical methods to measure folate species in blood, plasma and CSF; inherited and acquired causes of cerebral folate deficiency; and possible treatment options in those patients found to have cerebral folate deficiency.
Collapse
Affiliation(s)
- Simon Pope
- Neurometabolic Unit, National Hospital for Neurology, London, UK
| | - Rafael Artuch
- Clinical Biochemistry Department, Institut de Recerca Sant Joan de Déu and CIBERER, ISCIII, Barcelona, Spain
| | - Simon Heales
- Neurometabolic Unit, National Hospital for Neurology, London, UK
- Department of Chemical Pathology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
- Mitochondrial Research Group, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Shamima Rahman
- Mitochondrial Research Group, UCL Great Ormond Street Institute of Child Health, London, UK
- Department of Metabolic Medicine, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| |
Collapse
|
19
|
Verma V, Paul A, Amrapali Vishwanath A, Vaidya B, Clement JP. Understanding intellectual disability and autism spectrum disorders from common mouse models: synapses to behaviour. Open Biol 2019; 9:180265. [PMID: 31185809 PMCID: PMC6597757 DOI: 10.1098/rsob.180265] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Normal brain development is highly dependent on the timely coordinated actions of genetic and environmental processes, and an aberration can lead to neurodevelopmental disorders (NDDs). Intellectual disability (ID) and autism spectrum disorders (ASDs) are a group of co-occurring NDDs that affect between 3% and 5% of the world population, thus presenting a great challenge to society. This problem calls for the need to understand the pathobiology of these disorders and to design new therapeutic strategies. One approach towards this has been the development of multiple analogous mouse models. This review discusses studies conducted in the mouse models of five major monogenic causes of ID and ASDs: Fmr1, Syngap1, Mecp2, Shank2/3 and Neuroligins/Neurnexins. These studies reveal that, despite having a diverse molecular origin, the effects of these mutations converge onto similar or related aetiological pathways, consequently giving rise to the typical phenotype of cognitive, social and emotional deficits that are characteristic of ID and ASDs. This convergence, therefore, highlights common pathological nodes that can be targeted for therapy. Other than conventional therapeutic strategies such as non-pharmacological corrective methods and symptomatic alleviation, multiple studies in mouse models have successfully proved the possibility of pharmacological and genetic therapy enabling functional recovery.
Collapse
Affiliation(s)
- Vijaya Verma
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur, Bengaluru 560 064, Karnataka, India
| | - Abhik Paul
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur, Bengaluru 560 064, Karnataka, India
| | - Anjali Amrapali Vishwanath
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur, Bengaluru 560 064, Karnataka, India
| | - Bhupesh Vaidya
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur, Bengaluru 560 064, Karnataka, India
| | - James P Clement
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur, Bengaluru 560 064, Karnataka, India
| |
Collapse
|
20
|
Johannesen KM, Gardella E, Encinas AC, Lehesjoki A, Linnankivi T, Petersen MB, Lund ICB, Blichfeldt S, Miranda MJ, Pal DK, Lascelles K, Procopis P, Orsini A, Bonuccelli A, Giacomini T, Helbig I, Fenger CD, Sisodiya SM, Hernandez‐Hernandez L, Krithika S, Rumple M, Masnada S, Valente M, Cereda C, Giordano L, Accorsi P, Bürki SE, Mancardi M, Korff C, Guerrini R, Spiczak S, Hoffman‐Zacharska D, Mazurczak T, Coppola A, Buono S, Vecchi M, Hammer MF, Varesio C, Veggiotti P, Lal D, Brünger T, Zara F, Striano P, Rubboli G, Møller RS. The spectrum of intermediate
SCN
8A
‐related epilepsy. Epilepsia 2019; 60:830-844. [DOI: 10.1111/epi.14705] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 03/07/2019] [Accepted: 03/07/2019] [Indexed: 01/06/2023]
Affiliation(s)
- Katrine M. Johannesen
- Department of Epilepsy Genetics and Personalized TreatmentDanish Epilepsy Center Filadelfia Dianalund Denmark
- Institute for Regional Health ServicesUniversity of Southern Denmark Odense Denmark
| | - Elena Gardella
- Department of Epilepsy Genetics and Personalized TreatmentDanish Epilepsy Center Filadelfia Dianalund Denmark
- Institute for Regional Health ServicesUniversity of Southern Denmark Odense Denmark
| | - Alejandra C. Encinas
- Graduate Interdisciplinary Program of GeneticsUniversity of Arizona Tucson Arizona
| | - Anna‐Elina Lehesjoki
- Folkhälsan Research Center Helsinki Finland
- Research Programs Unit, Molecular Neurology and MedicumUniversity of Helsinki Helsinki Finland
| | - Tarja Linnankivi
- Department of Child NeurologyChildren's HospitalUniversity of Helsinki and Helsinki University Hospital Helsinki Finland
| | - Michael B. Petersen
- Department of Clinical GeneticsAalborg University Hospital Aalborg Denmark
- Department of Clinical MedicineAalborg University Aalborg Denmark
| | | | | | | | - Deb K. Pal
- Department of Basic and Clinical NeuroscienceInstitute of Psychiatry, Psychology, and NeuroscienceKing's College London London UK
- King's College Hospital London UK
- Evelina London Children's Hospital London UK
- Medical Research Council Centre for Neurodevelopmental DisordersKing's College London UK
| | - Karine Lascelles
- Department of Basic and Clinical NeuroscienceInstitute of Psychiatry, Psychology, and NeuroscienceKing's College London London UK
| | - Peter Procopis
- Children's Hospital Westmead, Sydney New South Wales Australia
- Discipline of Child and Adolescent HealthSydney Medical SchoolUniversity of Sydney Sydney New South Wales Australia
| | | | - Alice Bonuccelli
- Pediatric NeurologyPediatric ClinicUniversity of Pisa Pisa Italy
| | - Thea Giacomini
- Child Neuropsychiatry UnitDepartment of Neurosciences, Rehabilitation, Ophthalmology, Genetics, and Maternal and Children's SciencesGiannina Gaslini InstituteUniversity of Genoa Genoa Italy
| | - Ingo Helbig
- Department of NeuropediatricsUniversity Medical Center Schleswig Holstein Kiel Germany
- Division of NeurologyChildren's Hospital of Philadelphia Philadelphia Pennsylvania
| | - Christina D. Fenger
- Department of Epilepsy Genetics and Personalized TreatmentDanish Epilepsy Center Filadelfia Dianalund Denmark
| | - Sanjay M. Sisodiya
- Department of Clinical and Experimental EpilepsyUniversity College London Institute of Neurology London UK
- Chalfont Centre for Epilepsy Bucks UK
| | - Laura Hernandez‐Hernandez
- Department of Clinical and Experimental EpilepsyUniversity College London Institute of Neurology London UK
- Chalfont Centre for Epilepsy Bucks UK
| | - Sundararaman Krithika
- Department of Clinical and Experimental EpilepsyUniversity College London Institute of Neurology London UK
- Chalfont Centre for Epilepsy Bucks UK
| | - Melissa Rumple
- Pediatric NeurologyBanner Children's Specialists Glendale Arizona
| | - Silvia Masnada
- Department of Brain and Behavioral SciencesUniversity of Pavia Pavia Italy
| | - Marialuisa Valente
- Genomic and Postgenomic CenterScientific Institute for Research and Healthcare (IRCCS) Mondino Foundation Pavia Italy
| | - Cristina Cereda
- Genomic and Postgenomic CenterScientific Institute for Research and Healthcare (IRCCS) Mondino Foundation Pavia Italy
| | - Lucio Giordano
- Child Neurology and Psychiatry UnitCivilian Hospital Brescia Italy
| | - Patrizia Accorsi
- Child Neurology and Psychiatry UnitCivilian Hospital Brescia Italy
| | - Sarah E. Bürki
- Department of PediatricsDivision of Child NeurologyUniversity Children's Hospital BernUniversity of Bern Bern Switzerland
| | - Margherita Mancardi
- Unit of Child NeuropsychiatryEpilepsy CenterDepartment of Clinical and Surgical Neuroscience and RehabilitationGiannina Gaslini Institute Genoa Italy
| | - Christian Korff
- Child Neurology UnitUniversity Children's Hospital Geneva Switzerland
| | - Renzo Guerrini
- Neuroscience DepartmentChildren's Hospital Anna Meyer, University of Florence Florence Italy
| | - Sarah Spiczak
- Department of NeuropediatricsChristian Albrecht University Kiel Germany
- Northern German Epilepsy Center for Children and Adolescents Schwentinental Germany
| | | | - Tomasz Mazurczak
- Department of Neurology of Children and AdolescentsInstitute of Mother and Child Warsaw Poland
| | - Antonietta Coppola
- Department of Neuroscience and Reproductive and Odontostomatological SciencesFederico II University Naples Italy
| | - Salvatore Buono
- Neurology DivisionHospital of National Relevance (AORN), Santobono Pausilipon Naples Italy
| | - Marilena Vecchi
- Pediatric Clinic, Hospital CompanyUniversity of Padua Padua Italy
| | - Michael F. Hammer
- University of Arizona Genetic CoreUniversity of Arizona Tucson Arizona
| | - Costanza Varesio
- Brain and Behavior DepartmentUniversity of Pavia Pavia Italy
- Child and Adolescence Neurology DepartmentIRCCS C. Mondino National Neurological Institute Pavia Italy
| | - Pierangelo Veggiotti
- Department of Child NeurologyV. Buzzi Children's Hospital Milan Italy
- L. Sacco Department of Biomedical and Clinical SciencesUniversity of Milan Milan Italy
| | - Dennis Lal
- Epilepsy CenterNeurological InstituteCleveland Clinic Cleveland Ohio
- Genomic Medicine InstituteLerner Research Institute Cleveland Clinic Cleveland Ohio
- Stanley Center for Psychiatric ResearchBroad Institute of Massachusetts Institute of Technology and Harvard Cambridge Massachusetts
- Analytic and Translational Genetics UnitMassachusetts General Hospital Boston Massachusetts
- Cologne Center for GenomicsUniversity of Cologne Cologne Germany
| | - Tobias Brünger
- Cologne Center for GenomicsUniversity of Cologne Cologne Germany
| | - Federico Zara
- Laboratory of Neurogenetics and NeuroscienceDepartment of Head‐Neck and NeuroscienceGiannina Gaslini Institute Genoa Italy
| | - Pasquale Striano
- Pediatric NeurologyPediatric ClinicUniversity of Studies of Pisa Pisa Italy
| | - Guido Rubboli
- Department of Epilepsy Genetics and Personalized TreatmentDanish Epilepsy Center Filadelfia Dianalund Denmark
- University of Copenhagen Copenhagen Denmark
| | - Rikke S. Møller
- Department of Epilepsy Genetics and Personalized TreatmentDanish Epilepsy Center Filadelfia Dianalund Denmark
- Institute for Regional Health ServicesUniversity of Southern Denmark Odense Denmark
| |
Collapse
|
21
|
Tsang MH, Leung GK, Ho AC, Yeung K, Mak CC, Pei SL, Yu MH, Kan AS, Chan KY, Kwong KL, Lee S, Yung AW, Fung C, Chung BH. Exome sequencing identifies molecular diagnosis in children with drug-resistant epilepsy. Epilepsia Open 2019; 4:63-72. [PMID: 30868116 PMCID: PMC6398105 DOI: 10.1002/epi4.12282] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Revised: 10/09/2018] [Accepted: 10/27/2018] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE Early onset drug-resistant epilepsy is a neurologic disorder in which 2 antiepileptic drugs fail to maintain the seizure-free status of the patient. Heterogeneous clinical presentations make the diagnosis challenging. We aim to identify the underlying genetic causes of a pediatric cohort with drug-resistant epilepsy and evaluate whether the findings can provide information on patient management. METHODS We include patients with drug-resistant epilepsy onset before 18 years of age. Singleton clinical chromosomal microarray (CMA) followed by whole exome sequencing (WES) was performed using genomic DNA. In the first-tier analysis of the exome data, we aimed to identify disease-causing mutations in 546 genes known to cause, or to be associated with, epilepsy. For negative cases, we proceeded to exome-wide analysis. Rare coding variants were interrogated for pathogenicity based on the American College of Medical Genetics and Genomics (ACMG) guidelines. RESULTS We recruited 50 patients. We identified 6 pathogenic or likely pathogenic mutations, giving a diagnostic yield of 12%. Mutations were found in 6 different genes: SCN8A, SCN1A, MECP2, CDKL5, DEPDC5, and CHD2. The CDKL5 variant was found to be mosaic. One variant of unknown significance (VUS) in KCNT1 was found in a patient with compatible clinical features. Of note, a reported pathogenic SCN5A mutation known to contribute to Brugada syndrome, was also found in the patient with an SCN1A mutation. SIGNIFICANCE Our study suggests that singleton WES is an effective diagnostic tool for drug-resistant epilepsy. Genetic diagnosis can help to consolidate the clinical diagnosis, to facilitate phenotypic expansion, and to influence treatment and management options for seizure control in our patients. In our study, a significant portion of the genetic findings are known to be associated with an increased risk of sudden unexpected death in epilepsy (SUDEP). These findings could assist with more appropriate management in patients with epilepsy.
Collapse
Affiliation(s)
- Mandy Ho‐Yin Tsang
- Department of Paediatrics & Adolescent MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SARChina
| | - Gordon Ka‐Chun Leung
- Department of Paediatrics & Adolescent MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SARChina
| | - Alvin Chi‐Chung Ho
- Department of Paediatrics & Adolescent MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SARChina
| | - Kit‐San Yeung
- Department of Paediatrics & Adolescent MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SARChina
| | - Christopher Chun‐Yu Mak
- Department of Paediatrics & Adolescent MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SARChina
| | - Steven Lim‐Cho Pei
- Department of Paediatrics & Adolescent MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SARChina
| | - Mullin Ho‐Chung Yu
- Department of Paediatrics & Adolescent MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SARChina
| | - Anita Sik‐Yau Kan
- Department of Obstetrics and GynaecologyTsan Yuk HospitalHong Kong SARChina
| | | | - Karen Ling Kwong
- Department of Paediatrics & Adolescent MedicineTuen Mun HospitalHong KongHong Kong
| | - So‐Lun Lee
- Department of Paediatrics & Adolescent MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SARChina
- Duchess of Kent Children's HospitalHong Kong SARChina
| | - Ada Wing‐Yan Yung
- Department of Paediatrics & Adolescent MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SARChina
| | - Cheuk‐Wing Fung
- Department of Paediatrics & Adolescent MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SARChina
- Duchess of Kent Children's HospitalHong Kong SARChina
| | - Brian Hon‐Yin Chung
- Department of Paediatrics & Adolescent MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SARChina
- Duchess of Kent Children's HospitalHong Kong SARChina
| |
Collapse
|
22
|
Mu W, Schiess N, Orthmann-Murphy JL, El-Hattab AW. The utility of whole exome sequencing in diagnosing neurological disorders in adults from a highly consanguineous population. J Neurogenet 2019; 33:21-26. [PMID: 30724636 DOI: 10.1080/01677063.2018.1555249] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
There is increasing evidence that whole exome sequencing (WES) has a high diagnostic yield and is cost-efficient for individuals with neurological phenotypes. However, there is limited data on the use of WES in non-Western populations, including populations with a high rate of consanguinity. Retrospective chart review was performed on 24 adults with undiagnosed neurological symptoms evaluated in genetics and neurology clinics in a tertiary care facility on the Arabian Peninsula, and had WES between 2014 and 2016. Definitive diagnoses were made in 13/24 (54%) of cases. Of these, 5/13 (38%) revealed novel pathogenic variants. Of the known 19/24 (79%) consanguineous cases, diagnostic rate was slightly higher, 11/19 (58%) as compared to 2/5 (40%) among non-consanguineous cases. Autosomal recessive disorders comprised 10/13 (77%) of molecular diagnoses, all found to be due to homozygous pathogenic variants among consanguineous cases. WES in this cohort of adults with neurological symptoms had a high diagnostic rate likely due to high consanguinity rates in this population, as evidenced by the high diagnostic rate of homozygous pathogenic variants.
Collapse
Affiliation(s)
- Weiyi Mu
- a Institute of Genetic Medicine , Johns Hopkins University , Baltimore , MD , USA
| | - Nicoline Schiess
- b Department of Neurology , Johns Hopkins University , Baltimore , MD , USA
| | - Jennifer L Orthmann-Murphy
- b Department of Neurology , Johns Hopkins University , Baltimore , MD , USA.,c Department of Neurology , Hospital of the University of Pennsylvania , Philadelphia , PA , USA
| | - Ayman W El-Hattab
- d Division of Clinical Genetics and Metabolic Disorder , Tawam Hospital , Al-Ain , United Arab Emirates
| |
Collapse
|
23
|
Abstract
Epilepsy in infants and children is one of the most common and devastating neurological disorders. In the past, we had a limited understanding of the causes of epilepsy in pediatric patients, so we treated pediatric epilepsy according to seizure type. Now with new tools and tests, we are entering the age of precision medicine in pediatric epilepsy. In this review, we use the new etiological classification system proposed by the International League Against Epilepsy to review the advances in the diagnosis of pediatric epilepsy, describe new tools to identify seizure foci for epilepsy surgery, and define treatable epilepsy syndromes.
Collapse
Affiliation(s)
- Priya Sharma
- Department of Neurology, University of North Carolina School of Medicine, Physicians Office Building, Chapel Hill, NC, 27599-7025, USA
| | - Ammar Hussain
- Department of Neurology, University of North Carolina School of Medicine, Physicians Office Building, Chapel Hill, NC, 27599-7025, USA
| | - Robert Greenwood
- Department of Neurology & Pediatrics, University of North Carolina School of Medicine, 2141 Physicians Office Building, Chapel Hill, NC, 27599-7025, USA
| |
Collapse
|
24
|
Sánchez Fernández I, Loddenkemper T, Gaínza-Lein M, Sheidley BR, Poduri A. Diagnostic yield of genetic tests in epilepsy: A meta-analysis and cost-effectiveness study. Neurology 2019; 92:e418-e428. [PMID: 30610098 PMCID: PMC6369901 DOI: 10.1212/wnl.0000000000006850] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 08/30/2018] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVE To compare the cost-effectiveness of genetic testing strategies in patients with epilepsy of unknown etiology. METHODS This meta-analysis and cost-effectiveness study compared strategies involving 3 genetic tests: chromosomal microarray (CMA), epilepsy panel (EP) with deletion/duplication testing, and whole-exome sequencing (WES) in a cost-effectiveness model, using "no genetic testing" as a point of comparison. RESULTS Twenty studies provided information on the diagnostic yield of CMA (8 studies), EP (9 studies), and WES (6 studies). The diagnostic yield was highest for WES: 0.45 (95% confidence interval [CI]: 0.33-0.57) (0.32 [95% CI: 0.22-0.44] adjusting for potential publication bias), followed by EP: 0.23 (95% CI: 0.18-0.29), and CMA: 0.08 (95% CI: 0.06-0.12). The most cost-effective test was WES with an incremental cost-effectiveness ratio (ICER) of $15,000/diagnosis. However, after adjusting for potential publication bias, the most cost-effective test was EP (ICER: $15,848/diagnosis) followed by WES (ICER: $34,500/diagnosis). Among combination strategies, the most cost-effective strategy was WES, then if nondiagnostic, EP, then if nondiagnostic, CMA (ICER: $15,336/diagnosis), although adjusting for potential publication bias, the most cost-effective strategy was EP ± CMA ± WES (ICER: $18,385/diagnosis). While the cost-effectiveness of individual tests and testing strategies overlapped, CMA was consistently less cost-effective than WES and EP. CONCLUSION WES and EP are the most cost-effective genetic tests for epilepsy. Our analyses support, for a broad population of patients with unexplained epilepsy, starting with these tests. Although less expensive, CMA has lower yield, and its use as the first-tier test is thus not supported from a cost-effectiveness perspective.
Collapse
Affiliation(s)
- Iván Sánchez Fernández
- From the Epilepsy Genetics Program (B.R.S., A.P.), Division of Epilepsy and Clinical Neurophysiology (I.S.F., T.L., M.G.-L., B.R.S., A.P.), Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA; Department of Child Neurology (I.S.F.), Hospital Sant Joan de Déu, Universidad de Barcelona, Spain; and Facultad de Medicina (M.G.-L.), Universidad Austral de Chile, Valdivia
| | - Tobias Loddenkemper
- From the Epilepsy Genetics Program (B.R.S., A.P.), Division of Epilepsy and Clinical Neurophysiology (I.S.F., T.L., M.G.-L., B.R.S., A.P.), Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA; Department of Child Neurology (I.S.F.), Hospital Sant Joan de Déu, Universidad de Barcelona, Spain; and Facultad de Medicina (M.G.-L.), Universidad Austral de Chile, Valdivia
| | - Marina Gaínza-Lein
- From the Epilepsy Genetics Program (B.R.S., A.P.), Division of Epilepsy and Clinical Neurophysiology (I.S.F., T.L., M.G.-L., B.R.S., A.P.), Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA; Department of Child Neurology (I.S.F.), Hospital Sant Joan de Déu, Universidad de Barcelona, Spain; and Facultad de Medicina (M.G.-L.), Universidad Austral de Chile, Valdivia
| | - Beth Rosen Sheidley
- From the Epilepsy Genetics Program (B.R.S., A.P.), Division of Epilepsy and Clinical Neurophysiology (I.S.F., T.L., M.G.-L., B.R.S., A.P.), Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA; Department of Child Neurology (I.S.F.), Hospital Sant Joan de Déu, Universidad de Barcelona, Spain; and Facultad de Medicina (M.G.-L.), Universidad Austral de Chile, Valdivia
| | - Annapurna Poduri
- From the Epilepsy Genetics Program (B.R.S., A.P.), Division of Epilepsy and Clinical Neurophysiology (I.S.F., T.L., M.G.-L., B.R.S., A.P.), Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA; Department of Child Neurology (I.S.F.), Hospital Sant Joan de Déu, Universidad de Barcelona, Spain; and Facultad de Medicina (M.G.-L.), Universidad Austral de Chile, Valdivia.
| |
Collapse
|
25
|
Zheng Y, Chen B, Wan S, Xu H, Dang Y, Song T, Li Y, Zhang J. Detection of 21q11.2-q22.11 deletions in a fetus by NIPT. J Clin Lab Anal 2019; 33:e22711. [PMID: 30666717 PMCID: PMC6818560 DOI: 10.1002/jcla.22711] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 10/14/2018] [Accepted: 10/15/2018] [Indexed: 01/29/2023] Open
Abstract
Background Non‐invasive prenatal testing (NIPT) is extensively used in the detection of fetal trisomies 21, 18, and 13, which is promptly becoming a common clinical practice. Concerned about the clinical application of non‐invasive detection of the fetal autosomal duplications or deletion. Case Presentation A 34‐year‐old, healthy pregnant woman was referred to the First Affiliated Hospital of the Air Force Medical University. The ultrasound examination indicates that low‐lying placenta, the fetus has a left ventricular bright spot and small amount of pericardial effusion. NIPT was chosen to further screen for fetal chromosomal abnormalities. NIPT results indicated an approximately 18 Mb deletion, which was verified by prenatal diagnosis. The chromosome microarray analysis (CMA) result showed about 19.2 Mb deletions in 21q11.2‐q22.11. The karyotype analysis result showed 46,XN,del(21)(q11.2q22.1). Prenatal diagnosis was consistent with NIPT results, and the paternal karyotype revealed no obvious abnormalities. Conclusion In this study, we successfully detected and diagnosed deletions of large fragments in chromosome 21 in a fetus using NIPT. This indicates that NIPT can provide effective genetic information for detecting fetal subchromosomal deletions/duplications.
Collapse
Affiliation(s)
- Yunyun Zheng
- Department of Obstetrics and Gynecology, The First Affiliated Hospital Of Air Force Medical University, Xi'an, Shaanxi, China
| | - Biliang Chen
- Department of Obstetrics and Gynecology, The First Affiliated Hospital Of Air Force Medical University, Xi'an, Shaanxi, China
| | - Shanning Wan
- Department of Obstetrics and Gynecology, The First Affiliated Hospital Of Air Force Medical University, Xi'an, Shaanxi, China
| | - Hui Xu
- Department of Obstetrics and Gynecology, The First Affiliated Hospital Of Air Force Medical University, Xi'an, Shaanxi, China
| | - Yinghui Dang
- Department of Obstetrics and Gynecology, The First Affiliated Hospital Of Air Force Medical University, Xi'an, Shaanxi, China
| | - Tingting Song
- Department of Obstetrics and Gynecology, The First Affiliated Hospital Of Air Force Medical University, Xi'an, Shaanxi, China
| | - Yu Li
- Department of Obstetrics and Gynecology, The First Affiliated Hospital Of Air Force Medical University, Xi'an, Shaanxi, China
| | - Jianfang Zhang
- Department of Obstetrics and Gynecology, The First Affiliated Hospital Of Air Force Medical University, Xi'an, Shaanxi, China
| |
Collapse
|
26
|
Vlaskamp DRM, Shaw BJ, Burgess R, Mei D, Montomoli M, Xie H, Myers CT, Bennett MF, XiangWei W, Williams D, Maas SM, Brooks AS, Mancini GMS, van de Laar IMBH, van Hagen JM, Ware TL, Webster RI, Malone S, Berkovic SF, Kalnins RM, Sicca F, Korenke GC, van Ravenswaaij-Arts CMA, Hildebrand MS, Mefford HC, Jiang Y, Guerrini R, Scheffer IE. SYNGAP1 encephalopathy: A distinctive generalized developmental and epileptic encephalopathy. Neurology 2019; 92:e96-e107. [PMID: 30541864 PMCID: PMC6340340 DOI: 10.1212/wnl.0000000000006729] [Citation(s) in RCA: 107] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 08/27/2018] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To delineate the epileptology, a key part of the SYNGAP1 phenotypic spectrum, in a large patient cohort. METHODS Patients were recruited via investigators' practices or social media. We included patients with (likely) pathogenic SYNGAP1 variants or chromosome 6p21.32 microdeletions incorporating SYNGAP1. We analyzed patients' phenotypes using a standardized epilepsy questionnaire, medical records, EEG, MRI, and seizure videos. RESULTS We included 57 patients (53% male, median age 8 years) with SYNGAP1 mutations (n = 53) or microdeletions (n = 4). Of the 57 patients, 56 had epilepsy: generalized in 55, with focal seizures in 7 and infantile spasms in 1. Median seizure onset age was 2 years. A novel type of drop attack was identified comprising eyelid myoclonia evolving to a myoclonic-atonic (n = 5) or atonic (n = 8) seizure. Seizure types included eyelid myoclonia with absences (65%), myoclonic seizures (34%), atypical (20%) and typical (18%) absences, and atonic seizures (14%), triggered by eating in 25%. Developmental delay preceded seizure onset in 54 of 56 (96%) patients for whom early developmental history was available. Developmental plateauing or regression occurred with seizures in 56 in the context of a developmental and epileptic encephalopathy (DEE). Fifty-five of 57 patients had intellectual disability, which was moderate to severe in 50. Other common features included behavioral problems (73%); high pain threshold (72%); eating problems, including oral aversion (68%); hypotonia (67%); sleeping problems (62%); autism spectrum disorder (54%); and ataxia or gait abnormalities (51%). CONCLUSIONS SYNGAP1 mutations cause a generalized DEE with a distinctive syndrome combining epilepsy with eyelid myoclonia with absences and myoclonic-atonic seizures, as well as a predilection to seizures triggered by eating.
Collapse
Affiliation(s)
- Danique R M Vlaskamp
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Benjamin J Shaw
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Rosemary Burgess
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Davide Mei
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Martino Montomoli
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Han Xie
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Candace T Myers
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Mark F Bennett
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Wenshu XiangWei
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Danielle Williams
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Saskia M Maas
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Alice S Brooks
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Grazia M S Mancini
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Ingrid M B H van de Laar
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Johanna M van Hagen
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Tyson L Ware
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Richard I Webster
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Stephen Malone
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Samuel F Berkovic
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Renate M Kalnins
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Federico Sicca
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - G Christoph Korenke
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Conny M A van Ravenswaaij-Arts
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Michael S Hildebrand
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Heather C Mefford
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Yuwu Jiang
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Renzo Guerrini
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia
| | - Ingrid E Scheffer
- From the Epilepsy Research Centre (D.R.M.V., B.J.S., R.B., M.F.B., S.F.B., M.S.H., I.E.S.), Department of Medicine, University of Melbourne, Austin Health, Australia; Departments of Genetics (D.R.M.V., C.M.A.v.R.-A.) and Neurology (D.R.M.V.), University Medical Center Groningen, University of Groningen, the Netherlands; Pediatric Neurology Unit and Laboratories (D.M., M.M.) and Pediatric Neurology (R.G.), Neurogenetics and Neurobiology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Italy; Department of Pediatrics and Pediatric Epilepsy Centre (H.X., W.X.W., Y.J.), Peking University First Hospital, Beijing, China; Department of Pediatrics (C.T.M., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Population Health and Immunity Division (M.F.B.), Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology (M.F.B.), University of Melbourne, Australia; Caulfield (D.W.), Melbourne, Australia; Department of Clinical Genetics (S.M.M.), Academic Medical Centre, Amsterdam, the Netherlands; Department of Clinical Genetics (A.S.B., G.M.S.M., I.M.B.H.v.d.L.), Erasmus University Medical Centre, Rotterdam, the Netherlands; Department of Clinical Genetics (J.M.v.H.), VU University Medical Center, Amsterdam, the Netherlands; Tasmanian Health Service (T.L.W.), Women's and Children's Services, Launceston General Hospital, Tasmania, Australia; TY Nelson Department of Neurology and Neurosurgery (R.I.W.) and Institute of Neuroscience and Muscle Research (R.I.W.), Children's Hospital at Westmead, Sydney, Australia; Department of Neurosciences (S.M.), Lady Cilento Children's Hospital, Brisbane, Australia; Department of Anatomical Pathology (R.M.K.), Austin Hospital, Melbourne, Australia; IRCCS Stella Maris Foundation (F.S., R.G.), Pisa, Italy; Klinikum Oldenburg (G.C.K.), Zentrum für Kinder-und Jugendmedizin, Klinik für Neuropädiatrie u. angeborene Stoffwechselerkrankungen, Oldenburg, Germany; Centre of Epilepsy (Y.J.), Beijing Institute for Brain Disorders, China; Department of Paediatrics (I.E.S.), University of Melbourne, Royal Children's Hospital, Australia; and Florey Institute of Neurosciences and Mental Health (I.E.S.), Parkville, Australia.
| |
Collapse
|
27
|
Myers KA, Johnstone DL, Dyment DA. Epilepsy genetics: Current knowledge, applications, and future directions. Clin Genet 2018; 95:95-111. [PMID: 29992546 DOI: 10.1111/cge.13414] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Revised: 07/03/2018] [Accepted: 07/06/2018] [Indexed: 12/12/2022]
Abstract
The rapid pace of disease gene discovery has resulted in tremendous advances in the field of epilepsy genetics. Clinical testing with comprehensive gene panels, exomes, and genomes are now available and have led to higher diagnostic rates and insights into the underlying disease processes. As such, the contribution to the care of patients by medical geneticists, neurogeneticists and genetic counselors are significant; the dysmorphic examination, the necessary pre- and post-test counseling, the selection of the appropriate next-generation sequencing-based test(s), and the interpretation of sequencing results require a care provider to have a comprehensive working knowledge of the strengths and limitations of the available testing technologies. As the underlying mechanisms of the encephalopathies and epilepsies are better understood, there may be opportunities for the development of novel therapies based on an individual's own specific genotype. Drug screening with in vitro and in vivo models of epilepsy can potentially facilitate new treatment strategies. The future of epilepsy genetics will also probably include other-omic approaches such as transcriptomes, metabolomes, and the expanded use of whole genome sequencing to further improve our understanding of epilepsy and provide better care for those with the disease.
Collapse
Affiliation(s)
- K A Myers
- Department of Pediatrics, University of McGill, Montreal, Canada.,Research Institute of the McGill University Health Centre, Montreal, Canada
| | - D L Johnstone
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Canada
| | - D A Dyment
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Canada.,Department of Genetics, Children's Hospital of Eastern Ontario, Ottawa, Canada
| |
Collapse
|
28
|
Fogel BL. Genetic and genomic testing for neurologic disease in clinical practice. HANDBOOK OF CLINICAL NEUROLOGY 2018; 147:11-22. [PMID: 29325607 DOI: 10.1016/b978-0-444-63233-3.00002-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
The influence of genetics on neurologic disease is broad and it is becoming more common that clinicians are presented with a patient whose disease is likely of genetic origin. In the search for mutations causing Mendelian disorders, advances in genetic testing methodology have propelled modern neurologic practice beyond single-gene testing into the realm of genomic medicine, where routine evaluations encompass hundreds or thousands of genes, or even the entire exome, representing all protein-coding genes in the genome. The role of various single-gene, multigene, and genomic testing methods, including chromosomal microarray and next-generation sequencing, in the evaluation of neurologic disease is discussed here to provide a framework for their use in a modern neurologic practice. Understanding the inherent issues that arise during the interpretation of sequence variants as pathogenic or benign and the potential discovery of incidental medically relevant findings are important considerations for neurologists utilizing these tests clinically. Strategies for the evaluation of clinically heterogeneous disorders are presented to guide neurologists in the transition from single-gene to genomic considerations and toward the prospect of the widespread routine use of exome sequencing in the continuing goal to achieve more rapid and more precise diagnoses that will improve management and outcome in patients challenged by neurologic disease.
Collapse
Affiliation(s)
- Brent L Fogel
- Program in Neurogenetics, Departments of Neurology and Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA, United States.
| |
Collapse
|
29
|
Strande NT, Brnich SE, Roman TS, Berg JS. Navigating the nuances of clinical sequence variant interpretation in Mendelian disease. Genet Med 2018; 20:918-926. [PMID: 29988079 PMCID: PMC6679919 DOI: 10.1038/s41436-018-0100-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 06/12/2018] [Indexed: 12/24/2022] Open
Abstract
Understanding clinical genetic test results in the era of next-generation sequencing has become increasingly complex, necessitating clear and thorough guidelines for sequence variant interpretation. To meet this need the American College of Medical Genetics and Genomics (ACMG) and the Association for Molecular Pathology (AMP) published guidelines for a systematic approach for sequence variant interpretation in 2015. This framework is intended to be adaptable to any Mendelian condition, promoting transparency and consistency in variant interpretation, yet its comprehensive nature yields important challenges and caveats that end users must understand. In this review, we address some of these nuances and discuss the evolving efforts to refine and adapt this framework. We also consider the added complexity of distinguishing between variant-level interpretations and case-level conclusions, particularly in the context of the large gene panel approach to clinical diagnostics.
Collapse
Affiliation(s)
- Natasha T Strande
- Department of Pathology and Laboratory Medicine, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Sarah E Brnich
- Department of Genetics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Tamara S Roman
- Department of Genetics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Jonathan S Berg
- Department of Genetics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
| |
Collapse
|
30
|
Howell KB, Eggers S, Dalziel K, Riseley J, Mandelstam S, Myers CT, McMahon JM, Schneider A, Carvill GL, Mefford HC, Scheffer IE, Harvey AS. A population-based cost-effectiveness study of early genetic testing in severe epilepsies of infancy. Epilepsia 2018; 59:1177-1187. [PMID: 29750358 DOI: 10.1111/epi.14087] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/03/2018] [Indexed: 01/12/2023]
Abstract
OBJECTIVE The severe epilepsies of infancy (SEI) are a devastating group of disorders that pose a major care and economic burden on society; early diagnosis is critical for optimal management. This study sought to determine the incidence and etiologies of SEI, and model the yield and cost-effectiveness of early genetic testing. METHODS A population-based study was undertaken of the incidence, etiologies, and cost-effectiveness of a whole exome sequencing-based gene panel (targeted WES) in infants with SEI born during 2011-2013, identified through electroencephalography (EEG) and neonatal databases. SEI was defined as seizure onset before age 18 months, frequent seizures, epileptiform EEG, and failure of ≥2 antiepileptic drugs. Medical records, investigations, MRIs, and EEGs were analyzed, and genetic testing was performed if no etiology was identified. Economic modeling was performed to determine yield and cost-effectiveness of investigation of infants with unknown etiology at epilepsy onset, incorporating targeted WES at different stages of the diagnostic pathway. RESULTS Of 114 infants with SEI (incidence = 54/100 000 live births/y), the etiology was determined in 76 (67%): acquired brain injuries (n = 14), focal cortical dysplasias (n = 14), other brain malformations (n = 17), channelopathies (n = 11), chromosomal (n = 9), metabolic (n = 6), and other genetic (n = 5) disorders. Modeling showed that incorporating targeted WES increased diagnostic yield compared to investigation without targeted WES (48/86 vs 39/86). Early targeted WES had lower total cost ($677 081 U.S. dollars [USD] vs $738 136 USD) than late targeted WES. A pathway with early targeted WES and limited metabolic testing yielded 7 additional diagnoses compared to investigation without targeted WES (46/86 vs 39/86), with lower total cost ($455 597 USD vs $661 103 USD), lower cost per diagnosis ($9904 USD vs $16 951 USD), and a dominant cost-effectiveness ratio. SIGNIFICANCE Severe epilepsies occur in 1 in 2000 infants, with the etiology identified in two-thirds, most commonly malformative. Early use of targeted WES yields more diagnoses at lower cost. Early genetic diagnosis will enable timely administration of precision medicines, once developed, with the potential to improve long-term outcome.
Collapse
Affiliation(s)
- Katherine B Howell
- Department of Neurology, Royal Children's Hospital, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia.,Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Stefanie Eggers
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Kim Dalziel
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Melbourne School of Global and Population Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Jessica Riseley
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Simone Mandelstam
- Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia.,Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Medical Imaging, Royal Children's Hospital, Melbourne, Victoria, Australia.,Department of Radiology, University of Melbourne, Melbourne, Victoria, Australia.,Florey Institute of Neuroscience and Mental Health, Melbourne, Victoria, Australia
| | - Candace T Myers
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Jacinta M McMahon
- Department of Medicine, Epilepsy Research Centre, Austin Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Amy Schneider
- Department of Medicine, Epilepsy Research Centre, Austin Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Gemma L Carvill
- Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Heather C Mefford
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, USA
| | | | - Ingrid E Scheffer
- Department of Neurology, Royal Children's Hospital, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia.,Florey Institute of Neuroscience and Mental Health, Melbourne, Victoria, Australia.,Department of Medicine, Epilepsy Research Centre, Austin Health, University of Melbourne, Melbourne, Victoria, Australia
| | - A Simon Harvey
- Department of Neurology, Royal Children's Hospital, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia.,Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| |
Collapse
|
31
|
Pisani F, Percesepe A, Spagnoli C. Genetic diagnosis in neonatal-onset epilepsies: Back to the future. Eur J Paediatr Neurol 2018; 22:354-357. [PMID: 29501409 DOI: 10.1016/j.ejpn.2018.02.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 01/28/2018] [Accepted: 02/12/2018] [Indexed: 11/16/2022]
Abstract
Seizures are more frequent in newborns than in any other period of life. In most cases they are due to acute dysfunction of the central nervous system; however some can be true epileptic disorders with an early onset. Although rare, diagnosis of neonatal-onset epilepsies is rising as genetic testing increases. The spectrum of clinical severity associated with specific genes can vary widely with difficulties in providing genotype-phenotype correlations. Therefore, clinicians should strive in order to clearly delineate the clinical features associated with pathogenic genetic variants with the aim to guide the increasing use of genetic testing and improve clinical management.
Collapse
|
32
|
Genetics of Epilepsy in the Era of Precision Medicine: Implications for Testing, Treatment, and Genetic Counseling. CURRENT GENETIC MEDICINE REPORTS 2018. [DOI: 10.1007/s40142-018-0139-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
33
|
Tumienė B, Maver A, Writzl K, Hodžić A, Čuturilo G, Kuzmanić-Šamija R, Čulić V, Peterlin B. Diagnostic exome sequencing of syndromic epilepsy patients in clinical practice. Clin Genet 2018; 93:1057-1062. [PMID: 29286531 DOI: 10.1111/cge.13203] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 12/21/2017] [Accepted: 12/22/2017] [Indexed: 02/04/2023]
Abstract
Although genetic revolution of recent years has vastly expanded a list of genes implicated in epilepsies, complex architecture of epilepsy genetics is still largely unknown, consequently, universally accepted workflows for epilepsy genetic testing in a clinical practice are missing. We present a comprehensive NGS-based diagnostic approach addressing both the clinical and genetic heterogeneity of disorders involving epilepsy or seizures. A bioinformatic panel of 862 epilepsy- or seizure-associated genes was applied to Mendeliome (4813 genes) or whole-exome sequencing data as a first stage, while the second stage included untargeted variant interpretation. Eighty-six consecutive patients with epilepsy or seizures associated with neurodevelopmental disorders and/or congenital malformations were investigated. Of the 86 probands, 42 harbored pathogenic and likely pathogenic variants, giving a diagnostic yield of 49%. Two patients were diagnosed with pathogenic copy number variations and 2 had causative mitochondrial DNA variants. Eleven patients (13%) were diagnosed with diseases with specific treatments. Besides, genomic approach in diagnostics had multiple additional benefits due to mostly non-specific, overlapping, not full-blown phenotypes and abilities to diagnose novel and ultra rare epilepsy-associated diseases. Likely pathogenic variants were identified in SOX5 gene, not previously associated with epilepsy, and UBA5, a recently associated with epilepsy gene.
Collapse
Affiliation(s)
- B Tumienė
- Clinical Institute for Medical Genetics, University Medical Centre Ljubljana, Ljubljana, Slovenia.,Department of Human and Medical Genetics, Centre for Medical Genetics, Vilnius University, Vilnius, Lithuania
| | - A Maver
- Clinical Institute for Medical Genetics, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - K Writzl
- Clinical Institute for Medical Genetics, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - A Hodžić
- Clinical Institute for Medical Genetics, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - G Čuturilo
- Department of Medical Genetics, University Children's Hospital, Belgrade, Serbia
| | | | - V Čulić
- Department of Pediatrics, University Hospital Split, Split, Croatia
| | - B Peterlin
- Clinical Institute for Medical Genetics, University Medical Centre Ljubljana, Ljubljana, Slovenia
| |
Collapse
|
34
|
Efficient strategy for the molecular diagnosis of intractable early-onset epilepsy using targeted gene sequencing. BMC Med Genomics 2018; 11:6. [PMID: 29390993 PMCID: PMC5796507 DOI: 10.1186/s12920-018-0320-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 01/03/2018] [Indexed: 11/22/2022] Open
Abstract
Background We intended to evaluate diagnostic utility of a targeted gene sequencing by using next generation sequencing (NGS) panel in patients with intractable early-onset epilepsy (EOE) and find the efficient analytical step for increasing the diagnosis rate. Methods We assessed 74 patients with EOE whose seizures started before 3 years of age using a customized NGS panel that included 172 genes. Single nucleotide variants (SNVs) and exonic and chromosomal copy number variations (CNVs) were intensively examined with our customized pipeline and crosschecked with commercial or pre-built software. Variants were filtered and prioritized by in-depth clinical review, and finally classified according to the American College of Medical Genetics and Genomics guidelines. Each case was further discussed in a monthly consensus meeting that included the participation of all laboratory personnel, bioinformaticians, geneticists, and clinicians. Results The NGS panel identified 28 patients (37.8%) with genetic abnormalities; 25 patients had pathogenic or likely pathogenic SNVs in 17 genes including SXTBP1 (n = 3), CDKL5 (n = 2), KCNQ2 (n = 2), SCN1A (n = 2), SYNGAP1 (n = 2), GNAO1 (n = 2), KCNT1 (n = 2), BRAT1, WWOX, ZEB2, CHD2, PRICKLE2, COL4A1, DNM1, SCN8A, MECP2, SLC9A6 (n = 1). The other 3 patients had pathogenic CNVs (2 duplications and 1 deletion) with varying sizes (from 2.5 Mb to 12 Mb). The overall diagnostic yield was 37.8% after following our step-by-step approach for clinical consensus. Conclusions NGS is a useful diagnostic tool with great utility for patients with EOE. Diagnostic yields can be maximized with a standardized and team-based approach. Electronic supplementary material The online version of this article (10.1186/s12920-018-0320-7) contains supplementary material, which is available to authorized users.
Collapse
|
35
|
Palmer EE, Schofield D, Shrestha R, Kandula T, Macintosh R, Lawson JA, Andrews I, Sampaio H, Johnson AM, Farrar MA, Cardamone M, Mowat D, Elakis G, Lo W, Zhu Y, Ying K, Morris P, Tao J, Dias KR, Buckley M, Dinger ME, Cowley MJ, Roscioli T, Kirk EP, Bye A, Sachdev RK. Integrating exome sequencing into a diagnostic pathway for epileptic encephalopathy: Evidence of clinical utility and cost effectiveness. Mol Genet Genomic Med 2018; 6:186-199. [PMID: 29314763 PMCID: PMC5902395 DOI: 10.1002/mgg3.355] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 10/26/2017] [Accepted: 10/30/2017] [Indexed: 12/16/2022] Open
Abstract
Background Epileptic encephalopathies are a devastating group of neurological conditions in which etiological diagnosis can alter management and clinical outcome. Exome sequencing and gene panel testing can improve diagnostic yield but there is no cost‐effectiveness analysis of their use or consensus on how to best integrate these tests into clinical diagnostic pathways. Methods We conducted a retrospective cost‐effectiveness study comparing trio exome sequencing with a standard diagnostic approach, for a well‐phenotyped cohort of 32 patients with epileptic encephalopathy, who remained undiagnosed after “first‐tier” testing. Sensitivity analysis was included with a range of commercial exome and multigene panels. Results The diagnostic yield was higher for the exome sequencing (16/32; 50%) than the standard arm (2/32; 6.2%). The trio exome sequencing pathway was cost‐effective compared to the standard diagnostic pathway with a cost saving of AU$5,236 (95% confidence intervals $2,482; $9,784) per additional diagnosis; the standard pathway cost approximately 10 times more per diagnosis. Sensitivity analysis demonstrated that the majority of commercial exome sequencing and multigene panels studied were also cost‐effective. The clinical utility of all diagnoses was reported. Conclusion Our study supports the integration of exome sequencing and gene panel testing into the diagnostic pathway for epileptic encephalopathy, both in terms of cost effectiveness and clinical utility. We propose a diagnostic pathway that integrates initial rapid screening for treatable causes and comprehensive genomic screening. This study has important implications for health policy and public funding for epileptic encephalopathy and other neurological conditions.
Collapse
Affiliation(s)
- Elizabeth E Palmer
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia.,Genetics of Learning Disability Service, Waratah, NSW, Australia.,The Garvan Institute for Medical Research, Darlinghurst, Sydney, NSW, Australia
| | - Deborah Schofield
- The Garvan Institute for Medical Research, Darlinghurst, Sydney, NSW, Australia.,Faculty of Pharmacy, The University of Sydney, Sydney, NSW, Australia.,The Murdoch Children's Research Institute, Melbourne, Vic., Australia
| | - Rupendra Shrestha
- Faculty of Pharmacy, The University of Sydney, Sydney, NSW, Australia
| | - Tejaswi Kandula
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia
| | | | - John A Lawson
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia
| | - Ian Andrews
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia
| | - Hugo Sampaio
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia
| | - Alexandra M Johnson
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia
| | - Michelle A Farrar
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia
| | - Michael Cardamone
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia
| | - David Mowat
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia
| | | | - William Lo
- SEALS pathology, Randwick, NSW, Australia
| | - Ying Zhu
- Genetics of Learning Disability Service, Waratah, NSW, Australia.,SEALS pathology, Randwick, NSW, Australia
| | - Kevin Ying
- The Garvan Institute for Medical Research, Darlinghurst, Sydney, NSW, Australia
| | - Paula Morris
- The Garvan Institute for Medical Research, Darlinghurst, Sydney, NSW, Australia
| | - Jiang Tao
- The Garvan Institute for Medical Research, Darlinghurst, Sydney, NSW, Australia.,St Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Kerith-Rae Dias
- The Garvan Institute for Medical Research, Darlinghurst, Sydney, NSW, Australia
| | | | - Marcel E Dinger
- The Garvan Institute for Medical Research, Darlinghurst, Sydney, NSW, Australia.,St Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Mark J Cowley
- The Garvan Institute for Medical Research, Darlinghurst, Sydney, NSW, Australia.,St Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Tony Roscioli
- Sydney Children's Hospital, Randwick, NSW, Australia.,SEALS pathology, Randwick, NSW, Australia
| | - Edwin P Kirk
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia.,SEALS pathology, Randwick, NSW, Australia
| | - Ann Bye
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia
| | - Rani K Sachdev
- Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, UNSW Medicine, The University of New South Wales, Sydney, NSW, Australia
| |
Collapse
|
36
|
Freund M, Taylor A, Ng C, Little AR. The NIH NeuroBioBank: creating opportunities for human brain research. HANDBOOK OF CLINICAL NEUROLOGY 2018; 150:41-48. [PMID: 29496155 DOI: 10.1016/b978-0-444-63639-3.00004-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The National Institutes of Health (NIH) NeuroBioBank is a federally funded research resource for human neurologic diseases and disorders. This chapter will discuss the principles that guided the creation of the NIH NeuroBioBank and the rationale for the resource model selected. In addition, we will describe some performance metrics in the first 2 years and highlight recent advances in biomedical neuroscience that could only have been achieved using postmortem human tissues. The NIH NeuroBioBank was created in order to increase availability of high-quality postmortem human brain tissues to the research community across a broad spectrum of neurologic diseases and disorders, and to achieve economies of scale over previous funding and organizational models. In addition, we aim to increase public awareness about the value of human tissue donation for research by providing web-based information to the public and through active outreach to disease advocacy communities. Studies with human brain tissue have led to a rapid increase in our knowledge of the biologic differences between humans and are bridging the divide between humans and model organisms. Studies of human brain are beginning to give us a glimpse not only into what makes us uniquely human as well as how individual biology may be connected to health and disease.
Collapse
Affiliation(s)
- Michelle Freund
- National Institute of Mental Health, Rockville, MD, United States
| | - Anna Taylor
- National Institute of Neurological Disorders and Stroke, Rockville, MD, United States
| | - Cathy Ng
- National Institute of Mental Health, Rockville, MD, United States
| | - A Roger Little
- National Institute on Drug Abuse, Rockville, MD, United States.
| |
Collapse
|
37
|
Tan QKG, McConkie-Rosell A, Juusola J, Gustafson KE, Pizoli CE, Buckley AF, Jiang YH. The importance of managing the patient and not the gene: expanded phenotype of GLE1-associated arthrogryposis. Cold Spring Harb Mol Case Stud 2017; 3:mcs.a002063. [PMID: 28729373 PMCID: PMC5701308 DOI: 10.1101/mcs.a002063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 06/19/2017] [Indexed: 12/13/2022] Open
Abstract
GLE1 encodes a protein important for mRNA export and appears to play roles in translation initiation and termination as well. Pathogenic variants in GLE1 mutations have been associated with lethal contracture syndrome and lethal arthrogryposis with anterior horn cell disease; phenotypes reported in individuals include fetal akinesia and a severe form of motor neuron disease, typically presenting with prenatal symptoms and perinatal lethality. In this article, we identified biallelic missense mutations in GLE1 by trio whole-exome sequencing in an individual affected with congenital motor weakness and contractures as well as feeding and respiratory difficulties. Muscle biopsy was consistent with anterior horn cell disease and supported the pathogenicity of the sequence variants. Importantly, this individual survived past the perinatal period with respiratory support and currently demonstrates age-appropriate cognition and slow but steady motor developmental progress. We propose that pathogenic variants in GLE1 can be associated with a nonperinatal lethal motor phenotype, and affected individuals can demonstrate motor skill progression, unlike prototypical anterior horn cell diseases such as spinal muscular atrophy.
Collapse
Affiliation(s)
- Queenie K-G Tan
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Allyn McConkie-Rosell
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina 27710, USA
| | | | - Kathryn E Gustafson
- Department of Pediatrics, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Carolyn E Pizoli
- Division of Pediatric Neurology, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Anne F Buckley
- Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Yong-Hui Jiang
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina 27710, USA
| |
Collapse
|
38
|
Malcolmson J, Kleyner R, Tegay D, Adams W, Ward K, Coppinger J, Nelson L, Meisler MH, Wang K, Robison R, Lyon GJ. SCN8A mutation in a child presenting with seizures and developmental delays. Cold Spring Harb Mol Case Stud 2017; 2:a001073. [PMID: 27900360 PMCID: PMC5111007 DOI: 10.1101/mcs.a001073] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The SCN8A gene encodes the sodium voltage-gated channel alpha subunit 8. Mutations in this gene have been associated with early infantile epileptic encephalopathy type 13. With the use of whole-exome sequencing, a de novo missense mutation in SCN8A was identified in a 4-yr-old female who initially exhibited symptoms of epilepsy at the age of 5 mo that progressed to a severe condition with very little movement, including being unable to sit or walk on her own.
Collapse
Affiliation(s)
- Janet Malcolmson
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA;; Genetic Counseling Graduate Program, Long Island University (LIU), Brookville, New York 11548, USA
| | - Robert Kleyner
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
| | - David Tegay
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
| | - Whit Adams
- Utah Foundation for Biomedical Research, Salt Lake City, Utah 84107, USA
| | - Kenneth Ward
- Affiliated Genetics, Salt Lake City, Utah 84109, USA
| | | | - Lesa Nelson
- Affiliated Genetics, Salt Lake City, Utah 84109, USA
| | - Miriam H Meisler
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan 48109-5618, USA
| | - Kai Wang
- Utah Foundation for Biomedical Research, Salt Lake City, Utah 84107, USA;; Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, California 90089, USA;; Department of Psychiatry and Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA
| | - Reid Robison
- Utah Foundation for Biomedical Research, Salt Lake City, Utah 84107, USA
| | - Gholson J Lyon
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA;; Utah Foundation for Biomedical Research, Salt Lake City, Utah 84107, USA
| |
Collapse
|
39
|
Mutations of N-Methyl-D-Aspartate Receptor Subunits in Epilepsy. Neurosci Bull 2017; 34:549-565. [PMID: 29124671 DOI: 10.1007/s12264-017-0191-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 09/19/2017] [Indexed: 01/31/2023] Open
Abstract
Epilepsy is one of the most common neurological diseases. Of all cases, 70%-80% are considered to be due to genetic factors. In recent years, a large number of genes have been identified as being involved in epilepsy. Among them, N-methyl-D-aspartate receptor (NMDAR) subunit-encoding genes represent a large proportion, suggesting an important role for NMDARs in epilepsy. In this review, we summarize and analyze the genotypes, functional alterations, and clinical aspects of NMDAR subunit mutations/variants identified from patients with epilepsy. These data will help to throw light upon the pathogenicity of these NMDAR mutations and advance our understanding of the subtle and complicated role of NMDARs in epilepsy. It will also offer new insights into precision therapy for this disorder.
Collapse
|
40
|
Zahed H, Sparks TN, Li B, Alsadah A, Shieh JTC. Potential Role of Genomic Sequencing in the Early Diagnosis of Treatable Genetic Conditions. J Pediatr 2017; 189:222-226.e1. [PMID: 28947054 PMCID: PMC6037534 DOI: 10.1016/j.jpeds.2017.06.040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 04/02/2017] [Accepted: 06/15/2017] [Indexed: 12/18/2022]
Abstract
We present cases of 3 children diagnosed with the same genetic condition, Gitelman syndrome, at different stages using various genetic methods: panel testing, targeted single gene sequencing, and exome sequencing. We discuss the advantages and disadvantages of each method and review the potential of genomic sequencing for early disease detection.
Collapse
Affiliation(s)
- Hengameh Zahed
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, CA
| | - Teresa N. Sparks
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, CA
,Department of Obstetrics, Gynecology and Reproductive Medicine, University of California San Francisco, San Francisco, CA
| | - Ben Li
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, CA
,Department of Obstetrics, Gynecology and Reproductive Medicine, University of California San Francisco, San Francisco, CA
| | - Adnan Alsadah
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, CA
| | - Joseph T. C. Shieh
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, CA
,Institute for Human Genetics, Benioff Children’s Hospital San Francisco, University of California San Francisco, San Francisco, CA
| |
Collapse
|
41
|
Wang J, Gao H, Bao X, Zhang Q, Li J, Wei L, Wu X, Chen Y, Yu S. SCN8A mutations in Chinese patients with early onset epileptic encephalopathy and benign infantile seizures. BMC MEDICAL GENETICS 2017; 18:104. [PMID: 28923014 PMCID: PMC5604297 DOI: 10.1186/s12881-017-0460-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 09/08/2017] [Indexed: 11/23/2022]
Abstract
Background SCN8A mutations have recently been associated with epilepsy and neurodevelopmental disorders. This study aimed to broaden the phenotypic-spectrum of disease related with SCN8A mutations. Methods To identify the pathogenic gene of a Chinese family, in which six members suffered from epilepsy, whole-exome sequencing was performed. In addition, target next-generation sequencing (NGS) was performed on 178 sporadic patients, who had epilepsy of unknown etiology within 6 months after birth. A detailed clinical history was obtained. Results A heterozygous missense mutation of SCN8A was identified in the Chinese family. Six de novo mutations of SCN8A were detected in 6 sporadic patients with epilepsy. In the family, six members developed seizures within a few years after birth. Five of them had milder clinical performance, that they had normal cognition and developmental milestones, and seizure-free was achieved by mono-therapy. The other one affected member presented with refractory epilepsy and developmental regression. She died from sudden unexpected death in epilepsy (SUDEP) at 17-year-old. Clinical features of six sporadic patients with SCN8A mutations were diverse, ranging from severe epileptic encephalopathy to benign epilepsy with normal cognition. Seizures started at the mean age of 3.9 months (from 2 months to 6 months). Seizure-free was achieved in four of them by mono- or multi-antiepileptic drugs. Five of them demonstrated mild or severe psychomotor retardation, whereas the other one was normal in development and intelligence. Conclusions Our findings extend the spectrum of SCN8A mutations and the clinical features of patients with SCN8A mutations. The majority of SCN8A mutations were de novo, inherited mutations from the heterozygous parents can also occur. The phenotypic spectrum of SCN8A mutation varied largely. Most affected patients manifested as refractory epilepsy and severe intellectual disability, only a small number of patients presented with milder clinical patterns. Additionally, our study confirmed that the same mutation can lead to different phenotypes. Electronic supplementary material The online version of this article (10.1186/s12881-017-0460-1) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Jiaping Wang
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Hua Gao
- Center for Bioinformatics, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Xinhua Bao
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China.
| | - Qingping Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Jiarui Li
- Center for Bioinformatics, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Liping Wei
- Center for Bioinformatics, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China.
| | - Xiru Wu
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Yan Chen
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Shujie Yu
- Department of Neurology, Harbin Children's Hospital, Harbin, Heilongjiang Province, 150010, China
| |
Collapse
|
42
|
Said E, Chong JX, Hempel M, Denecke J, Soler P, Strom T, Nickerson DA, Kubisch C, Bamshad MJ, Lessel D. Survival beyond the perinatal period expands the phenotypes caused by mutations in GLE1. Am J Med Genet A 2017; 173:3098-3103. [PMID: 28884921 DOI: 10.1002/ajmg.a.38406] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 06/15/2017] [Accepted: 07/20/2017] [Indexed: 01/06/2023]
Abstract
Mutations in GLE1 underlie Lethal Congenital Contracture syndrome (LCCS) and Lethal Arthrogryposis with Anterior Horn Cell Disease (LAAHD). Both LCCS and LAAHD are characterized by reduced fetal movements, congenital contractures, and a severe form of motor neuron disease that results in fetal death or death in the perinatal period, respectively. We identified bi-allelic mutations in GLE1 in two unrelated individuals with motor delays, feeding difficulties, and respiratory insufficiency who survived beyond the perinatal period. Each affected child had missense variants predicted to result in amino acid substitutions near the C-terminus of GLE1 that are predicted to disrupt protein-protein interaction or GLE1 protein targeting. We hypothesize that mutations that preserve function of the coiled-coil domain of GLE1 cause LAAHD whereas mutations that abolish the function of the coiled-coil domain cause LCCS. The phenotype of LAAHD is now expanded to include multiple individuals surviving into childhood suggesting that LAAHD is a misnomer and should be re-named Arthrogryposis with Anterior Horn Cell Disease (AAHD).
Collapse
Affiliation(s)
- Edith Said
- Department of Anatomy and Cell Biology, University of Malta, Msida, Malta.,Section of Medical Genetics, Mater dei Hospital, Msida, Malta
| | - Jessica X Chong
- Department of Pediatrics, University of Washington, Seattle, Washington
| | - Maja Hempel
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jonas Denecke
- Department of Pediatrics, University Medical Center Eppendorf, Hamburg, Germany
| | - Paul Soler
- Department of Paediatics, Mater dei Hospital, Msida, Malta
| | - Tim Strom
- Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany.,Institute of Human Genetics, Technische Universität München, Munich, Germany
| | - Deborah A Nickerson
- Department of Genome Sciences, University of Washington, Seattle, Washington
| | - Christian Kubisch
- Department of Pediatrics, University Medical Center Eppendorf, Hamburg, Germany
| | | | - Michael J Bamshad
- Department of Pediatrics, University of Washington, Seattle, Washington.,Department of Genome Sciences, University of Washington, Seattle, Washington.,Division of Genetic Medicine, Seattle Children's Hospital, Seattle, Washington
| | - Davor Lessel
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| |
Collapse
|
43
|
Hewson S, Puka K, Mercimek-Mahmutoglu S. Variable expressivity of a likely pathogenic variant in KCNQ2 in a three-generation pedigree presenting with intellectual disability with childhood onset seizures. Am J Med Genet A 2017; 173:2226-2230. [PMID: 28602030 DOI: 10.1002/ajmg.a.38281] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 04/04/2017] [Accepted: 04/14/2017] [Indexed: 11/06/2022]
Abstract
KCNQ2 has been reported as a frequent cause of autosomal dominant benign familial neonatal seizures. De novo likely pathogenic variants in KCNQ2 have been described in neonatal or early infantile onset epileptic encephalopathy patients. Here, we report a three-generation family with six affected patients with a novel likely pathogenic variant (c.628C>T; p.Arg210Cys) in KCNQ2. Four family members, three adults and a child, presented with a childhood seizure onset with variability in the severity of seizures and response to treatment, intellectual disability (ID) as well as behavioral problems. The two youngest affected patients had a variable degree of global developmental delay with no seizures at their current age. This three-generation family with six affected members expands the phenotypic spectrum of KCNQ2 associated encephalopathy to KCNQ2 associated ID and or childhood onset epileptic encephalopathy. We think that KCNQ2 associated epileptic encephalopathy should be included in the differential diagnosis of childhood onset epilepsy and early onset global developmental delay, cognitive dysfunction, or ID. Furthermore, whole exome sequencing in families with ID and history of autosomal dominant inheritance pattern with or without seizures, may further broaden the phenotypic spectrum of KCNQ2 associated epileptic encephalopathy or encephalopathy.
Collapse
Affiliation(s)
- Stacy Hewson
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Klajdi Puka
- Department of Psychology, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Saadet Mercimek-Mahmutoglu
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada.,Genetics and Genome Biology, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
44
|
Balci T, Hartley T, Xi Y, Dyment D, Beaulieu C, Bernier F, Dupuis L, Horvath G, Mendoza-Londono R, Prasad C, Richer J, Yang XR, Armour C, Bareke E, Fernandez B, McMillan H, Lamont R, Majewski J, Parboosingh J, Prasad A, Rupar C, Schwartzentruber J, Smith A, Tétreault M, Innes A, Boycott K. Debunking Occam's razor: Diagnosing multiple genetic diseases in families by whole-exome sequencing. Clin Genet 2017; 92:281-289. [DOI: 10.1111/cge.12987] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 12/30/2016] [Accepted: 01/31/2017] [Indexed: 12/15/2022]
Affiliation(s)
- T.B. Balci
- Department of Genetics; Children's Hospital of Eastern Ontario; Ottawa Ontario Canada
| | - T. Hartley
- Children's Hospital of Eastern Ontario Research Institute; University of Ottawa; Ottawa Ontario Canada
| | - Y. Xi
- Children's Hospital of Eastern Ontario Research Institute; University of Ottawa; Ottawa Ontario Canada
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine; University of Calgary; Calgary Alberta Canada
| | - D.A. Dyment
- Department of Genetics; Children's Hospital of Eastern Ontario; Ottawa Ontario Canada
- Children's Hospital of Eastern Ontario Research Institute; University of Ottawa; Ottawa Ontario Canada
| | - C.L. Beaulieu
- Children's Hospital of Eastern Ontario Research Institute; University of Ottawa; Ottawa Ontario Canada
| | - F.P. Bernier
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine; University of Calgary; Calgary Alberta Canada
| | - L. Dupuis
- Division of Clinical and Metabolic Genetics; The Hospital for Sick Children; Toronto Ontario Canada
| | - G.A. Horvath
- Division of Biochemical Diseases, Department of Pediatrics; University of British Columbia and BC Children's Hospital; Vancouver British Columbia Canada
| | - R. Mendoza-Londono
- Division of Clinical and Metabolic Genetics; The Hospital for Sick Children; Toronto Ontario Canada
| | - C. Prasad
- London Health Sciences Centre; Western University; London Ontario Canada
| | - J. Richer
- Department of Genetics; Children's Hospital of Eastern Ontario; Ottawa Ontario Canada
| | - X.-R. Yang
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine; University of Calgary; Calgary Alberta Canada
| | - C.M. Armour
- Department of Genetics; Children's Hospital of Eastern Ontario; Ottawa Ontario Canada
| | - E. Bareke
- Department of Human Genetics; McGill University; Montréal Québec Canada
| | - B.A. Fernandez
- Disciplines of Genetics and Medicine, Faculty of Medicine; Memorial University of Newfoundland; St. John's Newfoundland Canada
| | - H.J. McMillan
- Children's Hospital of Eastern Ontario Research Institute; University of Ottawa; Ottawa Ontario Canada
| | - R.E. Lamont
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine; University of Calgary; Calgary Alberta Canada
| | - J. Majewski
- Department of Human Genetics; McGill University; Montréal Québec Canada
| | - J.S. Parboosingh
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine; University of Calgary; Calgary Alberta Canada
| | - A.N. Prasad
- London Health Sciences Centre; Western University; London Ontario Canada
| | - C.A. Rupar
- London Health Sciences Centre; Western University; London Ontario Canada
| | | | - A.C. Smith
- Children's Hospital of Eastern Ontario Research Institute; University of Ottawa; Ottawa Ontario Canada
| | - M. Tétreault
- Department of Human Genetics; McGill University; Montréal Québec Canada
| | - A.M. Innes
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine; University of Calgary; Calgary Alberta Canada
| | - K.M. Boycott
- Department of Genetics; Children's Hospital of Eastern Ontario; Ottawa Ontario Canada
- Children's Hospital of Eastern Ontario Research Institute; University of Ottawa; Ottawa Ontario Canada
| | | | | |
Collapse
|
45
|
Mei D, Parrini E, Marini C, Guerrini R. The Impact of Next-Generation Sequencing on the Diagnosis and Treatment of Epilepsy in Paediatric Patients. Mol Diagn Ther 2017; 21:357-373. [DOI: 10.1007/s40291-017-0257-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
46
|
Gao K, Tankovic A, Zhang Y, Kusumoto H, Zhang J, Chen W, XiangWei W, Shaulsky GH, Hu C, Traynelis SF, Yuan H, Jiang Y. A de novo loss-of-function GRIN2A mutation associated with childhood focal epilepsy and acquired epileptic aphasia. PLoS One 2017; 12:e0170818. [PMID: 28182669 PMCID: PMC5300259 DOI: 10.1371/journal.pone.0170818] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Accepted: 01/11/2017] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVE N-methyl-D-aspartate receptors (NMDAR) subunit GRIN2A/GluN2A mutations have been identified in patients with various neurological diseases, such as epilepsy and intellectual disability / developmental delay (ID/DD). In this study, we investigated the phenotype and underlying molecular mechanism of a GRIN2A missense mutation identified by next generation sequencing on idiopathic focal epilepsy using in vitro electrophysiology. METHODS Genomic DNA of patients with epilepsy and ID/DD were sequenced by targeted next-generation sequencing within 300 genes related to epilepsy and ID/DD. The effects of one missense GRIN2A mutation on NMDAR function were evaluated by two-electrode voltage clamp current recordings and whole cell voltage clamp current recordings. RESULTS We identified one de novo missense GRIN2A mutation (Asp731Asn, GluN2A(D731N)) in a child with unexplained epilepsy and DD. The D731N mutation is located in a portion of the agonist-binding domain (ABD) in the GluN2A subunit, which is the binding pocket for agonist glutamate. This residue in the ABD is conserved among vertebrate species and all other NMDAR subunits, suggesting an important role in receptor function. The proband shows developmental delay as well as EEG-confirmed seizure activity. Functional analyses reveal that the GluN2A(D731N) mutation decreases glutamate potency by over 3,000-fold, reduces amplitude of current response, shortens synaptic-like response time course, and decreases channel open probability, while enhancing sensitivity to negative allosteric modulators, including extracellular proton and zinc inhibition. The combined effects reduce NMDAR function. SIGNIFICANCE We identified a de novo missense mutation in the GRIN2A gene in a patient with childhood focal epilepsy and acquired epileptic aphasia. The mutant decreases NMDAR activation suggesting NMDAR hypofunction may contribute to the epilepsy pathogenesis.
Collapse
Affiliation(s)
- Kai Gao
- Department of Pediatrics and Pediatric Epilepsy Center, Peking University First Hospital, Beijing, China
| | - Anel Tankovic
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Yujia Zhang
- Department of Pediatrics and Pediatric Epilepsy Center, Peking University First Hospital, Beijing, China
| | - Hirofumi Kusumoto
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Jin Zhang
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Wenjuan Chen
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, United States of America
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Wenshu XiangWei
- Department of Pediatrics and Pediatric Epilepsy Center, Peking University First Hospital, Beijing, China
| | - Gil H. Shaulsky
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Chun Hu
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Stephen F. Traynelis
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, United States of America
- Center for Functional Evaluation of Rare Variant (CFERV), Emory University School of Medicine, Atlanta, GA, United States of America
| | - Hongjie Yuan
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, United States of America
- Center for Functional Evaluation of Rare Variant (CFERV), Emory University School of Medicine, Atlanta, GA, United States of America
| | - Yuwu Jiang
- Department of Pediatrics and Pediatric Epilepsy Center, Peking University First Hospital, Beijing, China
- Center of Epilepsy, Beijing Institute for Brain Disorders, Beijing, China
| |
Collapse
|
47
|
Reif PS, Tsai MH, Helbig I, Rosenow F, Klein KM. Precision medicine in genetic epilepsies: break of dawn? Expert Rev Neurother 2016; 17:381-392. [DOI: 10.1080/14737175.2017.1253476] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Philipp Sebastian Reif
- Epilepsy Center Frankfurt Rhine-Main, Department of Neurology, Center of Neurology and Neurosurgery, University Hospital, Goethe-University Frankfurt, Frankfurt, Germany
| | - Meng-Han Tsai
- Division of Brain Function & Epilepsy, Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Ingo Helbig
- Division of Neurology, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel and University Medical Center Schleswig-Holstein, Kiel, Germany
- Departments of Brain and Cognitive Sciences, Physiology and Cell Biology, Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Felix Rosenow
- Epilepsy Center Frankfurt Rhine-Main, Department of Neurology, Center of Neurology and Neurosurgery, University Hospital, Goethe-University Frankfurt, Frankfurt, Germany
- Epilepsy Center Hessen, Department of Neurology, University Hospitals Giessen & Marburg, and Philipps-University Marburg, Marburg, Germany
| | - Karl Martin Klein
- Epilepsy Center Frankfurt Rhine-Main, Department of Neurology, Center of Neurology and Neurosurgery, University Hospital, Goethe-University Frankfurt, Frankfurt, Germany
- Epilepsy Center Hessen, Department of Neurology, University Hospitals Giessen & Marburg, and Philipps-University Marburg, Marburg, Germany
| |
Collapse
|
48
|
Ortigoza Escobar JD, Pérez Dueñas B. Treatable Inborn Errors of Metabolism Due to Membrane Vitamin Transporters Deficiency. Semin Pediatr Neurol 2016; 23:341-350. [PMID: 28284395 DOI: 10.1016/j.spen.2016.11.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
B vitamins act as cofactors for strategic metabolic processes. The SLC19 gene family of solute carriers has a significant structural similarity, transporting substrates with different structure and ionic charge. Three proteins of this family are expressed ubiquitously and mediate the transport of 2 important water-soluble vitamins, folate, and thiamine. SLC19A1 transports folate and SLC19A2 and SLC19A3 transport thiamine. PCFT and FOLR1 ensure intestinal absorption and transport of folate through the blood-brain barrier and SLC19A25 transports thiamine into the mitochondria. Several damaging genetic defects in vitamin B transport and metabolism have been reported. The most relevant feature of thiamine and folate transport defects is that both of them are treatable disorders. In this article, we discuss the biology and transport of thiamine and folate, as well as the clinical phenotype of the genetic defects.
Collapse
Affiliation(s)
- Juan Darío Ortigoza Escobar
- Department of Child Neurology, Pediatric Research Institute, Hospital Sant Joan de Déu, University of Barcelona, Barcelona, Spain; Centre for Biomedical Research on Rare Diseases (CIBERER), Institute of Health Carlos III, Madrid, Spain
| | - Belén Pérez Dueñas
- Department of Child Neurology, Pediatric Research Institute, Hospital Sant Joan de Déu, University of Barcelona, Barcelona, Spain; Centre for Biomedical Research on Rare Diseases (CIBERER), Institute of Health Carlos III, Madrid, Spain.
| |
Collapse
|
49
|
Patel J, Mercimek-Mahmutoglu S. Epileptic Encephalopathy in Childhood: A Stepwise Approach for Identification of Underlying Genetic Causes. Indian J Pediatr 2016; 83:1164-74. [PMID: 26821542 DOI: 10.1007/s12098-015-1979-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 12/02/2015] [Indexed: 01/29/2023]
Abstract
Epilepsy is one of the most common neurological disorders in childhood. Epilepsy associated with global developmental delay and cognitive dysfunction is defined as epileptic encephalopathy. Certain inherited metabolic disorders presenting with epileptic encephalopathy can be treated with disease specific diet, vitamin, amino acid or cofactor supplementations. In those disorders, disease specific therapy is successful to achieve good seizure control and improve long-term neurodevelopmental outcome. For this reason, intractable epilepsy with global developmental delay or history of developmental regression warrants detailed metabolic investigations for the possibility of an underlying treatable inherited metabolic disorder, which should be undertaken as first line investigations. An underlying genetic etiology in epileptic encephalopathy has been supported by recent studies such as array comparative genomic hybridization, targeted next generation sequencing panels, whole exome and whole genome sequencing. These studies report a diagnostic yield up to 70%, depending on the applied genetic testing as well as number of patients enrolled. In patients with epileptic encephalopathy, a stepwise approach for diagnostic work-up will help to diagnose treatable inherited metabolic disorders quickly. Application of detailed genetic investigations such as targeted next generation sequencing as second line and whole exome sequencing as third line testing will diagnose underlying genetic disease which will help for genetic counseling as well as guide for prenatal diagnosis. Knowledge of underlying genetic cause will provide novel insights into the pathogenesis of epileptic encephalopathy and pave the ground towards the development of targeted neuroprotective treatment strategies to improve the health outcome of children with epileptic encephalopathy.
Collapse
Affiliation(s)
- Jaina Patel
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, M5G 1X8, Canada
| | - Saadet Mercimek-Mahmutoglu
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, M5G 1X8, Canada. .,Genetics and Genome Biology Program, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada.
| |
Collapse
|
50
|
Thiffault I, Speca DJ, Austin DC, Cobb MM, Eum KS, Safina NP, Grote L, Farrow EG, Miller N, Soden S, Kingsmore SF, Trimmer JS, Saunders CJ, Sack JT. A novel epileptic encephalopathy mutation in KCNB1 disrupts Kv2.1 ion selectivity, expression, and localization. ACTA ACUST UNITED AC 2016; 146:399-410. [PMID: 26503721 PMCID: PMC4621747 DOI: 10.1085/jgp.201511444] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A missense mutation in the pore-forming α subunit of a delayed rectifier Kv channel is associated with epileptic encephalopathy, alters the cation selectivity of voltage-gated currents, and disrupts channel expression and localization. The epileptic encephalopathies are a group of highly heterogeneous genetic disorders. The majority of disease-causing mutations alter genes encoding voltage-gated ion channels, neurotransmitter receptors, or synaptic proteins. We have identified a novel de novo pathogenic K+ channel variant in an idiopathic epileptic encephalopathy family. Here, we report the effects of this mutation on channel function and heterologous expression in cell lines. We present a case report of infantile epileptic encephalopathy in a young girl, and trio-exome sequencing to determine the genetic etiology of her disorder. The patient was heterozygous for a de novo missense variant in the coding region of the KCNB1 gene, c.1133T>C. The variant encodes a V378A mutation in the α subunit of the Kv2.1 voltage-gated K+ channel, which is expressed at high levels in central neurons and is an important regulator of neuronal excitability. We found that expression of the V378A variant results in voltage-activated currents that are sensitive to the selective Kv2 channel blocker guangxitoxin-1E. These voltage-activated Kv2.1 V378A currents were nonselective among monovalent cations. Striking cell background–dependent differences in expression and subcellular localization of the V378A mutation were observed in heterologous cells. Further, coexpression of V378A subunits and wild-type Kv2.1 subunits reciprocally affects their respective trafficking characteristics. A recent study reported epileptic encephalopathy-linked missense variants that render Kv2.1 a tonically activated, nonselective cation channel that is not voltage activated. Our findings strengthen the correlation between mutations that result in loss of Kv2.1 ion selectivity and development of epileptic encephalopathy. However, the strong voltage sensitivity of currents from the V378A mutant indicates that the loss of voltage-sensitive gating seen in all other reported disease mutants is not required for an epileptic encephalopathy phenotype. In addition to electrophysiological differences, we suggest that defects in expression and subcellular localization of Kv2.1 V378A channels could contribute to the pathophysiology of this KCNB1 variant.
Collapse
Affiliation(s)
- Isabelle Thiffault
- Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108
| | - David J Speca
- Department of Neurobiology, Physiology and Behavior, Department of Physiology and Membrane Biology, and Department of Anesthesiology and Pain Medicine, University of California, Davis, Davis, CA 95616
| | - Daniel C Austin
- Department of Neurobiology, Physiology and Behavior, Department of Physiology and Membrane Biology, and Department of Anesthesiology and Pain Medicine, University of California, Davis, Davis, CA 95616
| | - Melanie M Cobb
- Department of Neurobiology, Physiology and Behavior, Department of Physiology and Membrane Biology, and Department of Anesthesiology and Pain Medicine, University of California, Davis, Davis, CA 95616
| | - Kenneth S Eum
- Department of Neurobiology, Physiology and Behavior, Department of Physiology and Membrane Biology, and Department of Anesthesiology and Pain Medicine, University of California, Davis, Davis, CA 95616
| | - Nicole P Safina
- Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108
| | - Lauren Grote
- Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108
| | - Emily G Farrow
- Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108
| | - Neil Miller
- Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108
| | - Sarah Soden
- Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108 Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108 University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108
| | - Stephen F Kingsmore
- Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108 Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108 Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108 University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108
| | - James S Trimmer
- Department of Neurobiology, Physiology and Behavior, Department of Physiology and Membrane Biology, and Department of Anesthesiology and Pain Medicine, University of California, Davis, Davis, CA 95616 Department of Neurobiology, Physiology and Behavior, Department of Physiology and Membrane Biology, and Department of Anesthesiology and Pain Medicine, University of California, Davis, Davis, CA 95616
| | - Carol J Saunders
- Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108 Center for Pediatric Genomic Medicine, Department of Pathology and Laboratory Medicine, and Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108 University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108
| | - Jon T Sack
- Department of Neurobiology, Physiology and Behavior, Department of Physiology and Membrane Biology, and Department of Anesthesiology and Pain Medicine, University of California, Davis, Davis, CA 95616 Department of Neurobiology, Physiology and Behavior, Department of Physiology and Membrane Biology, and Department of Anesthesiology and Pain Medicine, University of California, Davis, Davis, CA 95616
| |
Collapse
|