1
|
Shao Q, Shi X, Ma B, Zeng J, Zheng A, Xie W. TBC1D24-related familial infantile multifocal myoclonus: Description of a new Chinese pedigree with a 20 year follow up. Epilepsy Res 2022; 182:106923. [DOI: 10.1016/j.eplepsyres.2022.106923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 03/24/2022] [Accepted: 04/05/2022] [Indexed: 11/26/2022]
|
2
|
Timpanaro T, La Mendola F, Billone S, Nora AD, Collotta A, Sauna A, Salafia S, Falsaperla R. TBC1D24 and Its Related Epileptic Encephalopathy. JOURNAL OF PEDIATRIC NEUROLOGY 2021. [DOI: 10.1055/s-0041-1728645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Abstract
TBC1D24, mapped to 16p13.3, encodes a protein containing a Tre2/Bub2/Cdc16 (TBC) domain, belonging to the super-family of Rab GTPase activating proteins (Rab-GAP). These proteins regulate various functions, including the regulation of the traffic of the vesicular membrane. Several TBC1D24 mutations have been related to autosomal recessive neurological disorders, including severe developmental encephalopathies with malignant early childhood epilepsy, benign epilepsy, epileptic encephalopathy, and a complex neurological syndrome characterized by deafness, onychodystrophy, bone and neurological degeneration. Mutations of TBC1D24 have also been reported in patients with nonsyndromic deafness with dominant or recessive inheritance. Mechanisms underlying TBC1D24-associated disorders and the functions of TBC1D24 products in the generation of such complex spectrum of diseases remain partly unclear and future studies are needed to clarify this aspect, in order to improve the management of seizures and for the prevention of complication (including death) of newly diagnosed patients affected by TBC1D24-related disorders.
Collapse
Affiliation(s)
- Tiziana Timpanaro
- Unit of Rare Diseases of the Nervous System in Childhood, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
| | | | - Sebastiano Billone
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Alessandra Di Nora
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Ausilia Collotta
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Alessandra Sauna
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | | | - Raffaele Falsaperla
- Unit of Pediatrics and Pediatric Emergency, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
- Unit of Neonatal Intensive Care and Neonatology, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
| |
Collapse
|
3
|
Lee TL, Lin PH, Chen PL, Hong JB, Wu CC. Hereditary Hearing Impairment with Cutaneous Abnormalities. Genes (Basel) 2020; 12:43. [PMID: 33396879 PMCID: PMC7823799 DOI: 10.3390/genes12010043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 12/25/2020] [Accepted: 12/26/2020] [Indexed: 12/15/2022] Open
Abstract
Syndromic hereditary hearing impairment (HHI) is a clinically and etiologically diverse condition that has a profound influence on affected individuals and their families. As cutaneous findings are more apparent than hearing-related symptoms to clinicians and, more importantly, to caregivers of affected infants and young individuals, establishing a correlation map of skin manifestations and their underlying genetic causes is key to early identification and diagnosis of syndromic HHI. In this article, we performed a comprehensive PubMed database search on syndromic HHI with cutaneous abnormalities, and reviewed a total of 260 relevant publications. Our in-depth analyses revealed that the cutaneous manifestations associated with HHI could be classified into three categories: pigment, hyperkeratosis/nail, and connective tissue disorders, with each category involving distinct molecular pathogenesis mechanisms. This outline could help clinicians and researchers build a clear atlas regarding the phenotypic features and pathogenetic mechanisms of syndromic HHI with cutaneous abnormalities, and facilitate clinical and molecular diagnoses of these conditions.
Collapse
Affiliation(s)
- Tung-Lin Lee
- Department of Medical Education, National Taiwan University Hospital, Taipei City 100, Taiwan;
| | - Pei-Hsuan Lin
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 11556, Taiwan;
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei City 100, Taiwan;
| | - Pei-Lung Chen
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei City 100, Taiwan;
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei City 100, Taiwan
- Department of Medical Genetics, National Taiwan University Hospital, Taipei 10041, Taiwan
- Department of Internal Medicine, National Taiwan University Hospital, Taipei 10041, Taiwan
| | - Jin-Bon Hong
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei City 100, Taiwan
- Department of Dermatology, National Taiwan University Hospital, Taipei City 100, Taiwan
| | - Chen-Chi Wu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 11556, Taiwan;
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei City 100, Taiwan;
- Department of Medical Genetics, National Taiwan University Hospital, Taipei 10041, Taiwan
- Department of Medical Research, National Taiwan University Biomedical Park Hospital, Hsinchu City 300, Taiwan
| |
Collapse
|
4
|
Harms FL, Parthasarathy P, Zorndt D, Alawi M, Fuchs S, Halliday BJ, McKeown C, Sampaio H, Radhakrishnan N, Radhakrishnan SK, Gorce M, Navet B, Ziegler A, Sachdev R, Robertson SP, Nampoothiri S, Kutsche K. Biallelic loss-of-function variants in TBC1D2B cause a neurodevelopmental disorder with seizures and gingival overgrowth. Hum Mutat 2020; 41:1645-1661. [PMID: 32623794 DOI: 10.1002/humu.24071] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 06/08/2020] [Accepted: 06/30/2020] [Indexed: 12/15/2022]
Abstract
The family of Tre2-Bub2-Cdc16 (TBC)-domain containing GTPase activating proteins (RABGAPs) is not only known as key regulatorof RAB GTPase activity but also has GAP-independent functions. Rab GTPases are implicated in membrane trafficking pathways, such as vesicular trafficking. We report biallelic loss-of-function variants in TBC1D2B, encoding a member of the TBC/RABGAP family with yet unknown function, as the underlying cause of cognitive impairment, seizures, and/or gingival overgrowth in three individuals from unrelated families. TBC1D2B messenger RNA amount was drastically reduced, and the protein was absent in fibroblasts of two patients. In immunofluorescence analysis, ectopically expressed TBC1D2B colocalized with vesicles positive for RAB5, a small GTPase orchestrating early endocytic vesicle trafficking. In two independent TBC1D2B CRISPR/Cas9 knockout HeLa cell lines that serve as cellular model of TBC1D2B deficiency, epidermal growth factor internalization was significantly reduced compared with the parental HeLa cell line suggesting a role of TBC1D2B in early endocytosis. Serum deprivation of TBC1D2B-deficient HeLa cell lines caused a decrease in cell viability and an increase in apoptosis. Our data reveal that loss of TBC1D2B causes a neurodevelopmental disorder with gingival overgrowth, possibly by deficits in vesicle trafficking and/or cell survival.
Collapse
Affiliation(s)
- Frederike L Harms
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Padmini Parthasarathy
- Department of Women's and Children's Health, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Dennis Zorndt
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Malik Alawi
- Bioinformatics Core, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sigrid Fuchs
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Benjamin J Halliday
- Department of Women's and Children's Health, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Colina McKeown
- Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, NSW, Australia
| | - Hugo Sampaio
- Department of Women and Children's Health, University of New South Wales, Randwick Campus, Randwick, NSW, Australia.,Sydney Children's Hospital, Randwick, NSW, Australia
| | - Natasha Radhakrishnan
- Department of Ophthalmology, Amrita Institute of Medical Sciences and Research Centre, Cochin, Kerala, India
| | - Suresh K Radhakrishnan
- Department of Neurology, Amrita Institute of Medical Sciences and Research Centre, Cochin, Kerala, India
| | - Magali Gorce
- Department of Metabolic Disease, Children University Hospital, Toulouse, France
| | - Benjamin Navet
- Department of Biochemistry and Genetics, University Hospital of Angers, Angers, France.,MitoLab, Institut MitoVasc, UMR CNRS6015, INSERM U1083, Angers, France
| | - Alban Ziegler
- Department of Biochemistry and Genetics, University Hospital of Angers, Angers, France.,MitoLab, Institut MitoVasc, UMR CNRS6015, INSERM U1083, Angers, France
| | - Rani Sachdev
- Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, NSW, Australia
| | - Stephen P Robertson
- Department of Women's and Children's Health, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Sheela Nampoothiri
- Department of Pediatric Genetics, Amrita Institute of Medical Sciences and Research Centre, Cochin, Kerala, India
| | - Kerstin Kutsche
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| |
Collapse
|
5
|
Lin L, Lyu Q, Kwan PY, Zhao J, Fan R, Chai A, Lai CSW, Chan YS, Shen X, Lai KO. The epilepsy and intellectual disability-associated protein TBC1D24 regulates the maintenance of excitatory synapses and animal behaviors. PLoS Genet 2020; 16:e1008587. [PMID: 32004315 PMCID: PMC7015432 DOI: 10.1371/journal.pgen.1008587] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 02/12/2020] [Accepted: 12/29/2019] [Indexed: 12/27/2022] Open
Abstract
Perturbation of synapse development underlies many inherited neurodevelopmental disorders including intellectual disability (ID). Diverse mutations on the human TBC1D24 gene are strongly associated with epilepsy and ID. However, the physiological function of TBC1D24 in the brain is not well understood, and there is a lack of genetic mouse model that mimics TBC1D24 loss-of-function for the study of animal behaviors. Here we report that TBC1D24 is present at the postsynaptic sites of excitatory synapses, where it is required for the maintenance of dendritic spines through inhibition of the small GTPase ARF6. Mice subjected to viral-mediated knockdown of TBC1D24 in the adult hippocampus display dendritic spine loss, deficits in contextual fear memory, as well as abnormal behaviors including hyperactivity and increased anxiety. Interestingly, we show that the protein stability of TBC1D24 is diminished by the disease-associated missense mutation that leads to F251L amino acid substitution. We further generate the F251L knock-in mice, and the homozygous mutants show increased neuronal excitability, spontaneous seizure and pre-mature death. Moreover, the heterozygous F251L knock-in mice survive into adulthood but display dendritic spine defects and impaired memory. Our findings therefore uncover a previously uncharacterized postsynaptic function of TBC1D24, and suggest that impaired dendritic spine maintenance contributes to the pathophysiology of individuals harboring TBC1D24 gene mutations. The F251L knock-in mice represent a useful animal model for investigation of the mechanistic link between TBC1D24 loss-of-function and neurodevelopmental disorders.
Collapse
Affiliation(s)
- Lianfeng Lin
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Quanwei Lyu
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Pui-Yi Kwan
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Junjun Zhao
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Ruolin Fan
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Anping Chai
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Cora Sau Wan Lai
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
- State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China
| | - Ying-Shing Chan
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
- State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China
| | - Xuting Shen
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Kwok-On Lai
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
- State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China
| |
Collapse
|
6
|
Zhang J, Chen J, Zeng Q, Zhang L, Tian X, Yang X, Yang Z, Wu Y, Wu X, Zhang Y. Infantile epilepsy with multifocal myoclonus caused by TBC1D24 mutations. Seizure 2019; 69:228-234. [DOI: 10.1016/j.seizure.2019.05.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 05/09/2019] [Accepted: 05/11/2019] [Indexed: 11/16/2022] Open
|
7
|
Mohandas N, Bass-Stringer S, Maksimovic J, Crompton K, Loke YJ, Walstab J, Reid SM, Amor DJ, Reddihough D, Craig JM. Epigenome-wide analysis in newborn blood spots from monozygotic twins discordant for cerebral palsy reveals consistent regional differences in DNA methylation. Clin Epigenetics 2018; 10:25. [PMID: 29484035 PMCID: PMC5824607 DOI: 10.1186/s13148-018-0457-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 02/12/2018] [Indexed: 12/21/2022] Open
Abstract
Background Cerebral palsy (CP) is a clinical description for a group of motor disorders that are heterogeneous with respect to causes, symptoms and severity. A diagnosis of CP cannot usually be made at birth and in some cases may be delayed until 2–3 years of age. This limits opportunities for early intervention that could otherwise improve long-term outcomes. CP has been recorded in monozygotic twins discordant for the disorder, indicating a potential role of non-genetic factors such as intrauterine infection, hypoxia-ischaemia, haemorrhage and thrombosis. The aim of this exploratory study was to utilise the discordant monozygotic twin model to understand and measure epigenetic changes associated with the development of CP. Methods We performed a genome-wide analysis of DNA methylation using the Illumina Infinium Human Methylation 450 BeadChip array with DNA from newborn blood spots of 15 monozygotic twin pairs who later became discordant for CP. Quality control and data preprocessing were undertaken using the minfi R package. Differential methylation analysis was performed using the remove unwanted variation (RUVm) method, taking twin pairing into account in order to identify CP-specific differentially methylated probes (DMPs), and bumphunter was performed to identify differentially methylated regions (DMRs). Results We identified 33 top-ranked DMPs based on a nominal p value cut-off of p < 1 × 10−4 and two DMRs (p < 1 × 10−3) associated with CP. The top-ranked probes related to 25 genes including HNRNPL, RASSF5, CD3D and KALRN involved in immune signalling pathways, in addition to TBC1D24, FBXO9 and VIPR2 previously linked to epileptic encephalopathy. Gene ontology and pathway analysis of top-ranked DMP-associated genes revealed enrichment of inflammatory signalling pathways, regulation of cytokine secretion and regulation of leukocyte-mediated immunity. We also identified two top-ranked DMRs including one on chromosome 6 within the promoter region of LTA gene encoding tumour necrosis factor-beta (TNF-β), an important regulator of inflammation and brain development. The second was within the transcription start site of the LIME1 gene, which plays a key role in inflammatory pathways such as MAPK signalling. CP-specific differential DNA methylation within one of our two top DMRs was validated using an independent platform, MassArray EpiTyper. Conclusions Ours is the first epigenome-wide association study of CP in disease-discordant monozygotic twin pairs and suggests a potential role for immune dysfunction in this condition. Electronic supplementary material The online version of this article (10.1186/s13148-018-0457-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Namitha Mohandas
- Environmental and Genetic Epidemiology Research, Murdoch Children's Research Institute, Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia.,2Department of Paediatrics, The University of Melbourne, Flemington Road, Parkville, Victoria 3052 Australia
| | - Sebastian Bass-Stringer
- Environmental and Genetic Epidemiology Research, Murdoch Children's Research Institute, Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia
| | - Jovana Maksimovic
- 2Department of Paediatrics, The University of Melbourne, Flemington Road, Parkville, Victoria 3052 Australia.,Bioinformatics Group, Murdoch Children's Research Institute, Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia
| | - Kylie Crompton
- 2Department of Paediatrics, The University of Melbourne, Flemington Road, Parkville, Victoria 3052 Australia.,4Developmental Disability and Rehabilitation Research, Murdoch Children's Research Institute, Flemington Road, Parkville, Victoria 3052 Australia.,5Neurodevelopment and Disability, The Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia
| | - Yuk J Loke
- Environmental and Genetic Epidemiology Research, Murdoch Children's Research Institute, Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia
| | - Janet Walstab
- 2Department of Paediatrics, The University of Melbourne, Flemington Road, Parkville, Victoria 3052 Australia.,4Developmental Disability and Rehabilitation Research, Murdoch Children's Research Institute, Flemington Road, Parkville, Victoria 3052 Australia
| | - Susan M Reid
- 2Department of Paediatrics, The University of Melbourne, Flemington Road, Parkville, Victoria 3052 Australia.,4Developmental Disability and Rehabilitation Research, Murdoch Children's Research Institute, Flemington Road, Parkville, Victoria 3052 Australia.,5Neurodevelopment and Disability, The Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia
| | - David J Amor
- 2Department of Paediatrics, The University of Melbourne, Flemington Road, Parkville, Victoria 3052 Australia.,4Developmental Disability and Rehabilitation Research, Murdoch Children's Research Institute, Flemington Road, Parkville, Victoria 3052 Australia.,5Neurodevelopment and Disability, The Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia
| | - Dinah Reddihough
- 2Department of Paediatrics, The University of Melbourne, Flemington Road, Parkville, Victoria 3052 Australia.,4Developmental Disability and Rehabilitation Research, Murdoch Children's Research Institute, Flemington Road, Parkville, Victoria 3052 Australia.,5Neurodevelopment and Disability, The Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia
| | - Jeffrey M Craig
- Environmental and Genetic Epidemiology Research, Murdoch Children's Research Institute, Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia.,2Department of Paediatrics, The University of Melbourne, Flemington Road, Parkville, Victoria 3052 Australia.,6Centre for Molecular and Medical Research, School of Medicine, Deakin University, Geelong, Victoria 3220 Australia
| |
Collapse
|
8
|
Rehman AU, Friedman TB, Griffith AJ. Unresolved questions regarding human hereditary deafness. Oral Dis 2017; 23:551-558. [PMID: 27259978 PMCID: PMC5136515 DOI: 10.1111/odi.12516] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 05/27/2016] [Accepted: 05/30/2016] [Indexed: 01/18/2023]
Abstract
Human hearing loss is a common neurosensory disorder about which many basic research and clinically relevant questions are unresolved. This review on hereditary deafness focuses on three examples considered at first glance to be uncomplicated, however, upon inspection, are enigmatic and ripe for future research efforts. The three examples of clinical and genetic complexities are drawn from studies of (i) Pendred syndrome/DFNB4 (PDS, OMIM 274600), (ii) Perrault syndrome (deafness and infertility) due to mutations of CLPP (PRTLS3, OMIM 614129), and (iii) the unexplained extensive clinical variability associated with TBC1D24 mutations. At present, it is unknown how different mutations of TBC1D24 cause non-syndromic deafness (DFNB86, OMIM 614617), epilepsy (OMIM 605021), epilepsy with deafness, or DOORS syndrome (OMIM 220500) that is characterized by deafness, onychodystrophy (alteration of toenail or fingernail morphology), osteodystrophy (defective development of bone), mental retardation, and seizures. A comprehensive understanding of the multifaceted roles of each gene associated with human deafness is expected to provide future opportunities for restoration as well as preservation of normal hearing.
Collapse
Affiliation(s)
- A U Rehman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - T B Friedman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - A J Griffith
- Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
9
|
Ngoh A, Bras J, Guerreiro R, McTague A, Ng J, Meyer E, Chong WK, Boyd S, MacLellan L, Kirkpatrick M, Kurian MA. TBC1D24 Mutations in a Sibship with Multifocal Polymyoclonus. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2017; 7:452. [PMID: 28428906 PMCID: PMC5395678 DOI: 10.7916/d8q52vbv] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 03/16/2017] [Indexed: 01/02/2023]
Abstract
Background Advances in molecular genetic technologies have improved our understanding of genetic causes of rare neurological disorders with features of myoclonus. Case Report A family with two affected siblings, presenting with multifocal polymyoclonus and neurodevelopmental delay, was recruited for whole-exome sequencing following unyielding diagnostic neurometabolic investigations. Compound heterozygous mutations in TBC1D24, a gene previously associated with various epilepsy phenotypes and hearing loss, were identified in both siblings. The mutations included a missense change c.457G>A (p.Glu157Lys), and a novel frameshift mutation c.545del (p.Thr182Serfs*6). Discussion We propose that TBC1D24-related diseases should be in the differential diagnosis for children with polymyoclonus.
Collapse
Affiliation(s)
- Adeline Ngoh
- Neurosciences Unit, University College London, Institute of Child Health, London, UK.,Department of Neurology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Jose Bras
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK.,Department of Medical Sciences and Institute of Biomedicine - iBiMED, University of Aveiro, Aveiro, Portugal
| | - Rita Guerreiro
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK.,Department of Medical Sciences and Institute of Biomedicine - iBiMED, University of Aveiro, Aveiro, Portugal
| | - Amy McTague
- Neurosciences Unit, University College London, Institute of Child Health, London, UK.,Department of Neurology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Joanne Ng
- Neurosciences Unit, University College London, Institute of Child Health, London, UK.,Department of Neurology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Esther Meyer
- Neurosciences Unit, University College London, Institute of Child Health, London, UK
| | - W Kling Chong
- Department of Neuroradiology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Stewart Boyd
- Department of Neurophysiology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | | | | | - Manju A Kurian
- Neurosciences Unit, University College London, Institute of Child Health, London, UK.,Department of Neurology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| |
Collapse
|
10
|
Chen T, Giri M, Xia Z, Subedi YN, Li Y. Genetic and epigenetic mechanisms of epilepsy: a review. Neuropsychiatr Dis Treat 2017; 13:1841-1859. [PMID: 28761347 PMCID: PMC5516882 DOI: 10.2147/ndt.s142032] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Epilepsy is a common episodic neurological disorder or condition characterized by recurrent epileptic seizures, and genetics seems to play a key role in its etiology. Early linkage studies have localized multiple loci that may harbor susceptibility genes to epilepsy, and mutational analyses have detected a number of mutations involved in both ion channel and nonion channel genes in patients with idiopathic epilepsy. Genome-wide studies of epilepsy have found copy number variants at 2q24.2-q24.3, 7q11.22, 15q11.2-q13.3, and 16p13.11-p13.2, some of which disrupt multiple genes, such as NRXN1, AUTS2, NLGN1, CNTNAP2, GRIN2A, PRRT2, NIPA2, and BMP5, implicated for neurodevelopmental disorders, including intellectual disability and autism. Unfortunately, only a few common genetic variants have been associated with epilepsy. Recent exome-sequencing studies have found some genetic mutations, most of which are located in nonion channel genes such as the LGI1, PRRT2, EFHC1, PRICKLE, RBFOX1, and DEPDC5 and in probands with rare forms of familial epilepsy, and some of these genes are involved with the neurodevelopment. Since epigenetics plays a role in neuronal function from embryogenesis and early brain development to tissue-specific gene expression, epigenetic regulation may contribute to the genetic mechanism of neurodevelopment through which a gene and the environment interacting with each other affect the development of epilepsy. This review focused on the analytic tools used to identify epilepsy and then provided a summary of recent linkage and association findings, indicating the existence of novel genes on several chromosomes for further understanding of the biology of epilepsy.
Collapse
Affiliation(s)
- Tian Chen
- Department of Health Management Center, Chongqing Three Gorges Central Hospital, Chongqing, People's Republic of China
| | - Mohan Giri
- National Center for Rheumatic Diseases, Ratopul, Gaushala, Kathmandu, Nepal
| | - Zhenyi Xia
- Department of Thoracic Surgery, Chongqing Three Gorges Central Hospital, Chongqing, People's Republic of China
| | - Yadu Nanda Subedi
- National Center for Rheumatic Diseases, Ratopul, Gaushala, Kathmandu, Nepal
| | - Yan Li
- Department of Health Management Center, Chongqing Three Gorges Central Hospital, Chongqing, People's Republic of China
| |
Collapse
|
11
|
Balestrini S, Milh M, Castiglioni C, Lüthy K, Finelli MJ, Verstreken P, Cardon A, Stražišar BG, Holder JL, Lesca G, Mancardi MM, Poulat AL, Repetto GM, Banka S, Bilo L, Birkeland LE, Bosch F, Brockmann K, Cross JH, Doummar D, Félix TM, Giuliano F, Hori M, Hüning I, Kayserili H, Kini U, Lees MM, Meenakshi G, Mewasingh L, Pagnamenta AT, Peluso S, Mey A, Rice GM, Rosenfeld JA, Taylor JC, Troester MM, Stanley CM, Ville D, Walkiewicz M, Falace A, Fassio A, Lemke JR, Biskup S, Tardif J, Ajeawung NF, Tolun A, Corbett M, Gecz J, Afawi Z, Howell KB, Oliver KL, Berkovic SF, Scheffer IE, de Falco FA, Oliver PL, Striano P, Zara F, Campeau PM, Sisodiya SM. TBC1D24 genotype-phenotype correlation: Epilepsies and other neurologic features. Neurology 2016; 87:77-85. [PMID: 27281533 PMCID: PMC4932231 DOI: 10.1212/wnl.0000000000002807] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 03/28/2016] [Indexed: 11/15/2022] Open
Abstract
Objective: To evaluate the phenotypic spectrum associated with mutations in TBC1D24. Methods: We acquired new clinical, EEG, and neuroimaging data of 11 previously unreported and 37 published patients. TBC1D24 mutations, identified through various sequencing methods, can be found online (http://lovd.nl/TBC1D24). Results: Forty-eight patients were included (28 men, 20 women, average age 21 years) from 30 independent families. Eighteen patients (38%) had myoclonic epilepsies. The other patients carried diagnoses of focal (25%), multifocal (2%), generalized (4%), and unclassified epilepsy (6%), and early-onset epileptic encephalopathy (25%). Most patients had drug-resistant epilepsy. We detail EEG, neuroimaging, developmental, and cognitive features, treatment responsiveness, and physical examination. In silico evaluation revealed 7 different highly conserved motifs, with the most common pathogenic mutation located in the first. Neuronal outgrowth assays showed that some TBC1D24 mutations, associated with the most severe TBC1D24-associated disorders, are not necessarily the most disruptive to this gene function. Conclusions: TBC1D24-related epilepsy syndromes show marked phenotypic pleiotropy, with multisystem involvement and severity spectrum ranging from isolated deafness (not studied here), benign myoclonic epilepsy restricted to childhood with complete seizure control and normal intellect, to early-onset epileptic encephalopathy with severe developmental delay and early death. There is no distinct correlation with mutation type or location yet, but patterns are emerging. Given the phenotypic breadth observed, TBC1D24 mutation screening is indicated in a wide variety of epilepsies. A TBC1D24 consortium was formed to develop further research on this gene and its associated phenotypes.
Collapse
|
12
|
Finelli MJ, Sanchez-Pulido L, Liu KX, Davies KE, Oliver PL. The Evolutionarily Conserved Tre2/Bub2/Cdc16 (TBC), Lysin Motif (LysM), Domain Catalytic (TLDc) Domain Is Neuroprotective against Oxidative Stress. J Biol Chem 2016; 291:2751-63. [PMID: 26668325 PMCID: PMC4742741 DOI: 10.1074/jbc.m115.685222] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 12/01/2015] [Indexed: 11/16/2022] Open
Abstract
Oxidative stress is a pathological feature of many neurological disorders; therefore, utilizing proteins that are protective against such cellular insults is a potentially valuable therapeutic approach. Oxidation resistance 1 (OXR1) has been shown previously to be critical for oxidative stress resistance in neuronal cells; deletion of this gene causes neurodegeneration in mice, yet conversely, overexpression of OXR1 is protective in cellular and mouse models of amyotrophic lateral sclerosis. However, the molecular mechanisms involved are unclear. OXR1 contains the Tre2/Bub2/Cdc16 (TBC), lysin motif (LysM), domain catalytic (TLDc) domain, a motif present in a family of proteins including TBC1 domain family member 24 (TBC1D24), a protein mutated in a range of disorders characterized by seizures, hearing loss, and neurodegeneration. The TLDc domain is highly conserved across species, although the structure-function relationship is unknown. To understand the role of this domain in the stress response, we carried out systematic analysis of all mammalian TLDc domain-containing proteins, investigating their expression and neuroprotective properties in parallel. In addition, we performed a detailed structural and functional study of this domain in which we identified key residues required for its activity. Finally, we present a new mouse insertional mutant of Oxr1, confirming that specific disruption of the TLDc domain in vivo is sufficient to cause neurodegeneration. Our data demonstrate that the integrity of the TLDc domain is essential for conferring neuroprotection, an important step in understanding the functional significance of all TLDc domain-containing proteins in the cellular stress response and disease.
Collapse
Affiliation(s)
- Mattéa J Finelli
- From the MRC Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, United Kingdom
| | - Luis Sanchez-Pulido
- From the MRC Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, United Kingdom
| | - Kevin X Liu
- From the MRC Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, United Kingdom
| | - Kay E Davies
- From the MRC Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, United Kingdom
| | - Peter L Oliver
- From the MRC Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, United Kingdom
| |
Collapse
|
13
|
Myers C, Mefford H. Genetic investigations of the epileptic encephalopathies. PROGRESS IN BRAIN RESEARCH 2016; 226:35-60. [DOI: 10.1016/bs.pbr.2016.04.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
14
|
Abstract
Epilepsy is a group of disorders characterized by recurrent seizures, and is one of the most common neurological conditions. The genetic basis of epilepsy is clear from epidemiological studies and from rare gene discoveries in large families. The three major classes of epilepsy disorders are genetic generalized, focal and encephalopathic epilepsies, with several specific disorders within each class. Advances in genomic technologies that facilitate genome-wide discovery of both common and rare variants have led to a rapid increase in our understanding of epilepsy genetics. Copy number variant and genome-wide association studies have contributed to our understanding of the complex genetic architecture of generalized epilepsy, while genetic insights into the focal epilepsies and epileptic encephalopathies have come primarily from exome sequencing. It is increasingly clear that epilepsy is genetically heterogeneous, and novel gene discoveries have moved the field beyond the known contribution of ion channels to implicate chromatin remodeling, transcriptional regulation and regulation of the mammalian target of rapamycin (mTOR) protein in the etiology of epilepsy. Such discoveries pave the way for new therapeutics, some of which are already being studied. In this review, we discuss the rapid pace of gene discovery in epilepsy, as facilitated by genomic technologies, and highlight several novel genes and potential therapies.
Collapse
Affiliation(s)
- Candace T Myers
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA, 98195, USA
| | - Heather C Mefford
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA, 98195, USA.
| |
Collapse
|
15
|
Doummar D, Mignot C, Apartis E, Villard L, Rodriguez D, Chantot-Bastauraud S, Burglen L. A Novel Homozygous TBC1D24 Mutation Causing Multifocal Myoclonus With Cerebellar Involvement. Mov Disord 2015. [PMID: 26207815 DOI: 10.1002/mds.26303] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Diane Doummar
- AP-HP, Service de Neuropédiatrie, Hôpital Trousseau, Paris, France.,Centre de Référence Neurogénétique de l'Enfant à l'adulte, Hôpital Trousseau, Paris, France.,Centre de Référence Malformations et Maladies Congénitales du Cervelet, Hôpital Trousseau, Paris, France
| | - Cyril Mignot
- AP-HP, Département de Génétique, Groupe Hospitalier Pitié-Salpêtrière, and Centre de Référence déficiences intellectuelles de causes rares, Paris, France
| | - Emmanuelle Apartis
- AP-HP, Unité de Neurophysiologie, Hôpital Saint-Antoine, Paris, France.,ICM INSERM, UMRS 975, et CNRS 7225-CRICM, Hôpital Pitié-Salpêtrière, Paris, France.,Université Pierre et Marie Curie-Paris-6, Paris, France
| | - Laurent Villard
- Aix-Marseille Université, Inserm, GMGF, UMR_S910, Marseille, France
| | - Diana Rodriguez
- AP-HP, Service de Neuropédiatrie, Hôpital Trousseau, Paris, France.,Centre de Référence Neurogénétique de l'Enfant à l'adulte, Hôpital Trousseau, Paris, France.,Centre de Référence Malformations et Maladies Congénitales du Cervelet, Hôpital Trousseau, Paris, France.,Université Pierre et Marie Curie-Paris-6, Paris, France.,Inserm U1141, Paris, France
| | | | - Lydie Burglen
- Centre de Référence Malformations et Maladies Congénitales du Cervelet, Hôpital Trousseau, Paris, France.,Inserm U1141, Paris, France.,AP-HP, Service de Génétique et d'Embryologie Médicale, Hôpital Armand Trousseau, Paris, France
| |
Collapse
|
16
|
Lesca G, Depienne C. Epilepsy genetics: the ongoing revolution. Rev Neurol (Paris) 2015; 171:539-57. [PMID: 26003806 DOI: 10.1016/j.neurol.2015.01.569] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 12/24/2014] [Accepted: 01/20/2015] [Indexed: 01/04/2023]
Abstract
Epilepsies have long remained refractory to gene identification due to several obstacles, including a highly variable inter- and intrafamilial expressivity of the phenotypes, a high frequency of phenocopies, and a huge genetic heterogeneity. Recent technological breakthroughs, such as array comparative genomic hybridization and next generation sequencing, have been leading, in the past few years, to the identification of an increasing number of genomic regions and genes in which mutations or copy-number variations cause various epileptic disorders, revealing an enormous diversity of pathophysiological mechanisms. The field that has undergone the most striking revolution is that of epileptic encephalopathies, for which most of causing genes have been discovered since the year 2012. Some examples are the continuous spike-and-waves during slow-wave sleep and Landau-Kleffner syndromes for which the recent discovery of the role of GRIN2A mutations has finally confirmed the genetic bases. These new technologies begin to be used for diagnostic applications, and the main challenge now resides in the interpretation of the huge mass of variants detected by these methods. The identification of causative mutations in epilepsies provides definitive confirmation of the clinical diagnosis, allows accurate genetic counselling, and sometimes permits the development of new appropriate and specific antiepileptic therapies. Future challenges include the identification of the genetic or environmental factors that modify the epileptic phenotypes caused by mutations in a given gene and the understanding of the role of somatic mutations in sporadic epilepsies.
Collapse
Affiliation(s)
- G Lesca
- Service de génétique, groupement hospitalier Est, hospices civils de Lyon, 59, boulevard Pinel, 69677 Bron, France; Université Claude-Bernard Lyon 1, 43, boulevard du 11-Novembre-1918, 69100 Villeurbanne, France; CRNL, CNRS UMR 5292, Inserm U1028, bâtiment IMBL, 11, avenue Jean-Capelle, 69621 Villeurbanne cedex, France.
| | - C Depienne
- Département de génétique et cytogénétique, hôpital Pitié-Salpêtrière, AP-HP, 47-83, boulevard de l'Hôpital, 75651 Paris cedex 13, France; Sorbonne universités, UPMC université Paris 06, 4, place Jussieu, 75005 Paris, France; ICM, CNRS UMR 7225, Inserm U1127, 47, boulevard de l'Hôpital, 75651 Paris cedex 13, France
| |
Collapse
|
17
|
Stražišar BG, Neubauer D, Paro Panjan D, Writzl K. Early-onset epileptic encephalopathy with hearing loss in two siblings with TBC1D24 recessive mutations. Eur J Paediatr Neurol 2015; 19:251-6. [PMID: 25557349 DOI: 10.1016/j.ejpn.2014.12.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 11/18/2014] [Accepted: 12/13/2014] [Indexed: 11/15/2022]
Abstract
BACKGROUND Recent studies have shown that recessive mutations in the TBC1D24 gene cause a variety of epilepsy syndromes, DOORS syndrome and nonsyndromic deafness. METHODS/RESULTS We report on two siblings with hypotonia, early-onset epileptic encephalopathy, and severe developmental delay. The patients presented with clonic and myoclonic jerks within 1 h after birth. The seizures were resistant to treatment. Audiologic examination showed bilateral sensorineural hearing loss in both siblings. Genetic analysis revealed compound heterozygous mutations in the TBC1D24 gene: a novel missense mutation c.32A > G (p.Asp11Gly) in exon 2 and a frameshift mutation c.1008delT (p.His336Glnfs*12) in exon 4. CONCLUSION This report supports previous observations that mutations in TBC1D24 cause diverse phenotypes. In fact, early-onset epileptic encephalopathy with sensorineural hearing loss is an additional phenotype observed in patients with recessive TBC1D24 mutations.
Collapse
Affiliation(s)
- Barbara Gnidovec Stražišar
- Department of Child, Adolescent & Developmental Neurology, University Children's Hospital, Ljubljana, Slovenia
| | - David Neubauer
- Department of Child, Adolescent & Developmental Neurology, University Children's Hospital, Ljubljana, Slovenia
| | - Darja Paro Panjan
- Department of Neonatology, University Children's Hospital, Ljubljana, Slovenia
| | - Karin Writzl
- Institute of Medical Genetics, University Medical Centre, Ljubljana, Slovenia.
| |
Collapse
|
18
|
Poulat AL, Ville D, de Bellescize J, André-Obadia N, Cacciagli P, Milh M, Villard L, Lesca G. Homozygous TBC1D24 mutation in two siblings with familial infantile myoclonic epilepsy (FIME) and moderate intellectual disability. Epilepsy Res 2015; 111:72-7. [PMID: 25769375 DOI: 10.1016/j.eplepsyres.2015.01.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 01/10/2015] [Accepted: 01/19/2015] [Indexed: 10/24/2022]
Abstract
Mutations in the TBC1D24 gene were first reported in an Italian family with a unique epileptic phenotype consisting of drug-responsive, early-onset idiopathic myoclonic seizures. Patients presented with isolated bilateral or focal myoclonia, which could evolve to long-lasting attacks without loss of consciousness, with a peculiar reflex component, and were associated with generalized tonic-clonic seizures. This entity was named "familial infantile myoclonic epilepsy" (FIME). More recently, TBC1D24 mutations have been shown to cause a variable range of disorders, including epilepsy of various seizure types and severity, non-syndromic deafness, and DOORS syndrome. We report on the electro-clinical features of two brothers, born to first-cousin parents, affected with infantile-onset myoclonic epilepsy. The peculiar epileptic presentation prompted us to perform direct sequencing of the TBC1D24 gene. The patients had very early onset of focal myoclonic fits with variable topography, lasting a few minutes to several hours, without loss of consciousness, which frequently evolved to generalized myoclonus or myoclonic status. Reflex myoclonia were noticed in one patient. Neurological outcome was marked by moderate intellectual disability. Despite the high frequency of seizures, repeated EEG recordings showed normal background rhythm and rare interictal spikes and waves. We found a homozygous missense mutation, c.457G>A/p.Glu153Lys, in the two affected brothers. This observation combined with recent data from the literature, suggest that mutations in TBCD24 cause a pathological continuum, with FIME at the "benign" end and severe drug-refractory epileptic encephalopathy on the severe end. Early-onset myoclonic epilepsy with focal and generalized myoclonic seizures is a common characteristic of this continuum.
Collapse
Affiliation(s)
- Anne-Lise Poulat
- Department of Pediatric Neurology, Groupement Hospitalier Est, Hospices Civils de Lyon, Lyon, France; Neurophysiology and Epilepsy Unit, Neurological Hospital P. Wertheimer, Hospices Civils de Lyon, Lyon, France
| | - Dorothée Ville
- Department of Pediatric Neurology, Groupement Hospitalier Est, Hospices Civils de Lyon, Lyon, France; Neurophysiology and Epilepsy Unit, Neurological Hospital P. Wertheimer, Hospices Civils de Lyon, Lyon, France
| | - Julitta de Bellescize
- Epilepsy, Sleep and Pediatric Neurophysiology Dpt., Groupement Hospitalier Est, Hospices Civils de Lyon, Lyon, France; Neurophysiology and Epilepsy Unit, Neurological Hospital P. Wertheimer, Hospices Civils de Lyon, Lyon, France
| | - Nathalie André-Obadia
- Department Epilepsy, Sleep and Functional Neurological Explorations, Groupement Hospitalier Est, Hospices Civils de Lyon, Lyon, France; Neurophysiology and Epilepsy Unit, Neurological Hospital P. Wertheimer, Hospices Civils de Lyon, Lyon, France
| | - Pierre Cacciagli
- INSERM, GMGF UMR_S 910, 13385, Aix Marseille Université, Marseille, France; Neurophysiology and Epilepsy Unit, Neurological Hospital P. Wertheimer, Hospices Civils de Lyon, Lyon, France
| | - Mathieu Milh
- INSERM, GMGF UMR_S 910, 13385, Aix Marseille Université, Marseille, France; Service de Neurologie Pédiatrique, Hopital de la Timone-Enfants, APHM, Marseille, France; Neurophysiology and Epilepsy Unit, Neurological Hospital P. Wertheimer, Hospices Civils de Lyon, Lyon, France
| | - Laurent Villard
- INSERM, GMGF UMR_S 910, 13385, Aix Marseille Université, Marseille, France; Neurophysiology and Epilepsy Unit, Neurological Hospital P. Wertheimer, Hospices Civils de Lyon, Lyon, France
| | - Gaetan Lesca
- Department of Medical Genetics, Hospices Civils de Lyon, Lyon, France; Université Lyon 1, Lyon, France; Neurophysiology and Epilepsy Unit, Neurological Hospital P. Wertheimer, Hospices Civils de Lyon, Lyon, France.
| |
Collapse
|
19
|
Muona M, Berkovic SF, Dibbens LM, Oliver KL, Maljevic S, Bayly MA, Joensuu T, Canafoglia L, Franceschetti S, Michelucci R, Markkinen S, Heron SE, Hildebrand MS, Andermann E, Andermann F, Gambardella A, Tinuper P, Licchetta L, Scheffer IE, Criscuolo C, Filla A, Ferlazzo E, Ahmad J, Ahmad A, Baykan B, Said E, Topcu M, Riguzzi P, King MD, Ozkara C, Andrade DM, Engelsen BA, Crespel A, Lindenau M, Lohmann E, Saletti V, Massano J, Privitera M, Espay AJ, Kauffmann B, Duchowny M, Møller RS, Straussberg R, Afawi Z, Ben-Zeev B, Samocha KE, Daly MJ, Petrou S, Lerche H, Palotie A, Lehesjoki AE. A recurrent de novo mutation in KCNC1 causes progressive myoclonus epilepsy. Nat Genet 2014; 47:39-46. [PMID: 25401298 DOI: 10.1038/ng.3144] [Citation(s) in RCA: 206] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 10/16/2014] [Indexed: 12/14/2022]
Abstract
Progressive myoclonus epilepsies (PMEs) are a group of rare, inherited disorders manifesting with action myoclonus, tonic-clonic seizures and ataxia. We sequenced the exomes of 84 unrelated individuals with PME of unknown cause and molecularly solved 26 cases (31%). Remarkably, a recurrent de novo mutation, c.959G>A (p.Arg320His), in KCNC1 was identified as a new major cause for PME. Eleven unrelated exome-sequenced (13%) and two affected individuals in a secondary cohort (7%) had this mutation. KCNC1 encodes KV3.1, a subunit of the KV3 voltage-gated potassium ion channels, which are major determinants of high-frequency neuronal firing. Functional analysis of the Arg320His mutant channel showed a dominant-negative loss-of-function effect. Ten cases had pathogenic mutations in known PME-associated genes (NEU1, NHLRC1, AFG3L2, EPM2A, CLN6 and SERPINI1). Identification of mutations in PRNP, SACS and TBC1D24 expand their phenotypic spectra to PME. These findings provide insights into the molecular genetic basis of PME and show the role of de novo mutations in this disease entity.
Collapse
Affiliation(s)
- Mikko Muona
- 1] Institute for Molecular Medicine Finland, University of Helsinki, Helsinki, Finland. [2] Folkhälsan Institute of Genetics, Helsinki, Finland. [3] Neuroscience Center, University of Helsinki, Helsinki, Finland. [4] Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
| | - Samuel F Berkovic
- Epilepsy Research Center, Department of Medicine, University of Melbourne, Austin Health, Heidelberg, Victoria, Australia
| | - Leanne M Dibbens
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Karen L Oliver
- Epilepsy Research Center, Department of Medicine, University of Melbourne, Austin Health, Heidelberg, Victoria, Australia
| | - Snezana Maljevic
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Marta A Bayly
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Tarja Joensuu
- 1] Folkhälsan Institute of Genetics, Helsinki, Finland. [2] Neuroscience Center, University of Helsinki, Helsinki, Finland. [3] Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
| | - Laura Canafoglia
- Department of Neurophysiopathology, C. Besta Foundation Neurological Institute, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS), Milan, Italy
| | - Silvana Franceschetti
- Department of Neurophysiopathology, C. Besta Foundation Neurological Institute, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS), Milan, Italy
| | - Roberto Michelucci
- Neurology Unit, IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy
| | - Salla Markkinen
- 1] Folkhälsan Institute of Genetics, Helsinki, Finland. [2] Neuroscience Center, University of Helsinki, Helsinki, Finland. [3] Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
| | - Sarah E Heron
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Michael S Hildebrand
- Epilepsy Research Center, Department of Medicine, University of Melbourne, Austin Health, Heidelberg, Victoria, Australia
| | - Eva Andermann
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Frederick Andermann
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | | | - Paolo Tinuper
- 1] Neurology Unit, IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy. [2] Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Laura Licchetta
- 1] Neurology Unit, IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy. [2] Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Ingrid E Scheffer
- 1] Epilepsy Research Center, Department of Medicine, University of Melbourne, Austin Health, Heidelberg, Victoria, Australia. [2] Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia. [3] Department of Pediatrics, Royal Children's Hospital, University of Melbourne, Melbourne, Victoria, Australia
| | - Chiara Criscuolo
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, Federico II University, Naples, Italy
| | - Alessandro Filla
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, Federico II University, Naples, Italy
| | - Edoardo Ferlazzo
- 1] Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy. [2] Regional Epilepsy Center, Bianchi-Melacrino-Morelli Hospital, Reggio Calabria, Italy
| | - Jamil Ahmad
- Department of Biotechnology and Informatics, Balochistan University of Information Technology, Engineering and Management Sciences, Quetta, Pakistan
| | - Adeel Ahmad
- Department of Medicine, Mayo Hospital, Lahore, Pakistan
| | - Betul Baykan
- 1] Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey. [2] Epilepsy Center (EPIMER), Istanbul University, Istanbul, Turkey
| | - Edith Said
- 1] Department of Anatomy and Cell Biology, University of Malta, Msida, Malta. [2] Section of Medical Genetics, Mater dei Hospital, Msida, Malta
| | - Meral Topcu
- Division of Pediatric Neurology, Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Patrizia Riguzzi
- Neurology Unit, IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy
| | - Mary D King
- 1] Department of Neurology, Temple Street Children's University Hospital, Dublin, Ireland. [2] Academic Centre on Rare Diseases, School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - Cigdem Ozkara
- Department of Neurology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey
| | - Danielle M Andrade
- Division of Neurology, Department of Medicine, University of Toronto, Toronto Western Hospital, Krembil Neurosciences Program, Toronto, Ontario, Canada
| | - Bernt A Engelsen
- 1] Department of Clinical Medicine, University of Bergen, Bergen, Norway. [2] Department of Neurology, Haukeland University Hospital, Bergen, Norway
| | | | - Matthias Lindenau
- Department of Neurology and Epileptology, Epilepsy Center Hamburg-Alsterdorf, Hamburg, Germany
| | - Ebba Lohmann
- 1] Department of Neurology and Epileptology, Epilepsy Center Hamburg-Alsterdorf, Hamburg, Germany. [2] Department of Neurodegenerative Diseases, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany. [3] German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | - Veronica Saletti
- Developmental Neurology Unit, C. Besta Foundation Neurological Institute, IRCCS, Milan, Italy
| | - João Massano
- 1] Department of Neurology, Centro Hospitalar São João, Porto, Portugal. [2] Department of Clinical Neurosciences and Mental Health, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Michael Privitera
- Epilepsy Center, University of Cincinnati Neuroscience Institute, Cincinnati, Ohio, USA
| | - Alberto J Espay
- Gardner Center for Parkinson Disease and Movement Disorders, University of Cincinnati, Cincinnati, Ohio, USA
| | | | - Michael Duchowny
- 1] Brain Institute, Miami Children's Hospital, Miami, Florida, USA. [2] Department of Neurology, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Rikke S Møller
- 1] Danish Epilepsy Centre, Dianalund, Denmark. [2] Institute of Regional Health Services Research, University of Southern Denmark, Odense, Denmark
| | - Rachel Straussberg
- 1] Neurogenetic Clinic, Child Neurology Institute, Schneider Children's Medical Center of Israel, Petah Tiqvah, Israel. [2] Sackler School of Medicine, Tel-Aviv University, Ramat Aviv, Israel
| | - Zaid Afawi
- 1] Sackler School of Medicine, Tel-Aviv University, Ramat Aviv, Israel. [2] Zlotowski Center for Neuroscience, Ben-Gurion University, Beer-Sheva, Israel
| | - Bruria Ben-Zeev
- 1] Sackler School of Medicine, Tel-Aviv University, Ramat Aviv, Israel. [2] Pediatric Neurology Unit, Edmond and Lilly Safra Children's Hospital, Sheba Medical Center, Ramat-Gan, Israel
| | - Kaitlin E Samocha
- 1] Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA. [2] Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA. [3] Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA. [4] Program in Genetics and Genomics, Biological and Biomedical Sciences, Harvard Medical School, Boston, Massachusetts, USA
| | - Mark J Daly
- 1] Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA. [2] Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA. [3] Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA. [4] Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA
| | - Steven Petrou
- 1] Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia. [2] Centre for Neural Engineering, University of Melbourne, Melbourne, Victoria, Australia
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Aarno Palotie
- 1] Institute for Molecular Medicine Finland, University of Helsinki, Helsinki, Finland. [2] Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA. [3] Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA. [4] Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA. [5] Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, UK. [6] Psychiatric and Neurodevelopmental Genetics Unit, Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts, USA. [7] Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Anna-Elina Lehesjoki
- 1] Folkhälsan Institute of Genetics, Helsinki, Finland. [2] Neuroscience Center, University of Helsinki, Helsinki, Finland. [3] Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
| |
Collapse
|
20
|
TBC1D24 regulates neuronal migration and maturation through modulation of the ARF6-dependent pathway. Proc Natl Acad Sci U S A 2014; 111:2337-42. [PMID: 24469796 DOI: 10.1073/pnas.1316294111] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Alterations in the formation of brain networks are associated with several neurodevelopmental disorders. Mutations in TBC1 domain family member 24 (TBC1D24) are responsible for syndromes that combine cortical malformations, intellectual disability, and epilepsy, but the function of TBC1D24 in the brain remains unknown. We report here that in utero TBC1D24 knockdown in the rat developing neocortex affects the multipolar-bipolar transition of neurons leading to delayed radial migration. Furthermore, we find that TBC1D24-knockdown neurons display an abnormal maturation and retain immature morphofunctional properties. TBC1D24 interacts with ADP ribosylation factor (ARF)6, a small GTPase crucial for membrane trafficking. We show that in vivo, overexpression of the dominant-negative form of ARF6 rescues the neuronal migration and dendritic outgrowth defects induced by TBC1D24 knockdown, suggesting that TBC1D24 prevents ARF6 activation. Overall, our findings demonstrate an essential role of TBC1D24 in neuronal migration and maturation and highlight the physiological relevance of the ARF6-dependent membrane-trafficking pathway in brain development.
Collapse
|
21
|
Berkovic SF, Gecz J. Phenotype–genotype complexities: opening DOORS. Lancet Neurol 2014; 13:24-5. [DOI: 10.1016/s1474-4422(13)70237-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
22
|
Campeau PM, Kasperaviciute D, Lu JT, Burrage LC, Kim C, Hori M, Powell BR, Stewart F, Félix TM, van den Ende J, Wisniewska M, Kayserili H, Rump P, Nampoothiri S, Aftimos S, Mey A, Nair LDV, Begleiter ML, De Bie I, Meenakshi G, Murray ML, Repetto GM, Golabi M, Blair E, Male A, Giuliano F, Kariminejad A, Newman WG, Bhaskar SS, Dickerson JE, Kerr B, Banka S, Giltay JC, Wieczorek D, Tostevin A, Wiszniewska J, Cheung SW, Hennekam RC, Gibbs RA, Lee BH, Sisodiya SM. The genetic basis of DOORS syndrome: an exome-sequencing study. Lancet Neurol 2013; 13:44-58. [PMID: 24291220 PMCID: PMC3895324 DOI: 10.1016/s1474-4422(13)70265-5] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Background Deafness, onychodystrophy, osteodystrophy, mental retardation, and seizures (DOORS) syndrome is a rare autosomal recessive disorder of unknown cause. We aimed to identify the genetic basis of this syndrome by sequencing most coding exons in affected individuals. Methods Through a search of available case studies and communication with collaborators, we identified families that included at least one individual with at least three of the five main features of the DOORS syndrome: deafness, onychodystrophy, osteodystrophy, intellectual disability, and seizures. Participants were recruited from 26 centres in 17 countries. Families described in this study were enrolled between Dec 1, 2010, and March 1, 2013. Collaborating physicians enrolling participants obtained clinical information and DNA samples from the affected child and both parents if possible. We did whole-exome sequencing in affected individuals as they were enrolled, until we identified a candidate gene, and Sanger sequencing to confirm mutations. We did expression studies in human fibroblasts from one individual by real-time PCR and western blot analysis, and in mouse tissues by immunohistochemistry and real-time PCR. Findings 26 families were included in the study. We did exome sequencing in the first 17 enrolled families; we screened for TBC1D24 by Sanger sequencing in subsequent families. We identified TBC1D24 mutations in 11 individuals from nine families (by exome sequencing in seven families, and Sanger sequencing in two families). 18 families had individuals with all five main features of DOORS syndrome, and TBC1D24 mutations were identified in half of these families. The seizure types in individuals with TBC1D24 mutations included generalised tonic-clonic, complex partial, focal clonic, and infantile spasms. Of the 18 individuals with DOORS syndrome from 17 families without TBC1D24 mutations, eight did not have seizures and three did not have deafness. In expression studies, some mutations abrogated TBC1D24 mRNA stability. We also detected Tbc1d24 expression in mouse phalangeal chondrocytes and calvaria, which suggests a role of TBC1D24 in skeletogenesis. Interpretation Our findings suggest that mutations in TBC1D24 seem to be an important cause of DOORS syndrome and can cause diverse phenotypes. Thus, individuals with DOORS syndrome without deafness and seizures but with the other features should still be screened for TBC1D24 mutations. More information is needed to understand the cellular roles of TBC1D24 and identify the genes responsible for DOORS phenotypes in individuals who do not have a mutation in TBC1D24. Funding US National Institutes of Health, the CIHR (Canada), the NIHR (UK), the Wellcome Trust, the Henry Smith Charity, and Action Medical Research.
Collapse
Affiliation(s)
- Philippe M Campeau
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Dalia Kasperaviciute
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK
| | - James T Lu
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA; Department of Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Lindsay C Burrage
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Choel Kim
- Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA
| | - Mutsuki Hori
- Department of Pediatrics, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan
| | | | - Fiona Stewart
- Genetics Service, Belfast City Hospital, Belfast, Ireland
| | - Têmis Maria Félix
- Medical Genetics Service, Clinical Hospital of Porto Alegre, Porto Alegre, Brazil
| | - Jenneke van den Ende
- Department of Medical Genetics, University Hospital Antwerp, 2650 Antwerp, Belgium
| | - Marzena Wisniewska
- Department of Medical Genetics, Poznañ University of Medical Sciences, Poznañ, Poland
| | - Hülya Kayserili
- Medical Genetics Department, Istanbul Medical Faculty, Istanbul University, Turkey
| | - Patrick Rump
- Department of Genetics, University of Groningen, Groningen, Netherlands
| | - Sheela Nampoothiri
- Department of Pediatric Genetics, Amrita Institute of Medical Sciences and Research Centre, Kerala, India
| | - Salim Aftimos
- Genetic Health Service New Zealand-Northern Hub, Auckland City Hospital, Auckland, New Zealand
| | - Antje Mey
- Pediatric Neurology, Braunschweig Hospital, Braunschweig, Germany
| | - Lal D V Nair
- Department of Pediatrics, Saveetha Medical College and Hospital, Saveetha University, Chennai, Tamil Nadu, 600077, India
| | - Michael L Begleiter
- Division of Genetics, Children's Mercy Hospitals and Clinics and the University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA
| | - Isabelle De Bie
- Department of Medical Genetics, Montreal Children's Hospital, McGill University Health Center, Quebec, Canada
| | - Girish Meenakshi
- Department of Pediatrics, NKP Salve Institute of Medical Sciences and Lata Mangeshkar Hospital, Maharashtra, India
| | - Mitzi L Murray
- University of Washington Medical Center, Seattle, WA, USA
| | - Gabriela M Repetto
- Center for Human Genetics, Facultad de Medicina, Clínica Alemana-Universidad del Desarrollo, Santiago, Chile
| | - Mahin Golabi
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA
| | - Edward Blair
- Department of Clinical Genetics, Churchill Hospital, Oxford, UK
| | - Alison Male
- Clinical Genetics Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Fabienne Giuliano
- Centre Référence Anomalie Développement et Syndromes Malformatifs, Centre Hospitalier Universitaire de Nice, France
| | | | - William G Newman
- Manchester Centre for Genomic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; Manchester Centre for Genomic Centre for Genetic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; St Mary's Hospital, Manchester Academic Health Science Centre, Manchester, UK
| | - Sanjeev S Bhaskar
- Manchester Centre for Genomic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; Manchester Centre for Genomic Centre for Genetic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; St Mary's Hospital, Manchester Academic Health Science Centre, Manchester, UK
| | - Jonathan E Dickerson
- Manchester Centre for Genomic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; Manchester Centre for Genomic Centre for Genetic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; St Mary's Hospital, Manchester Academic Health Science Centre, Manchester, UK
| | - Bronwyn Kerr
- Manchester Centre for Genomic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; Manchester Centre for Genomic Centre for Genetic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; St Mary's Hospital, Manchester Academic Health Science Centre, Manchester, UK
| | - Siddharth Banka
- Manchester Centre for Genomic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; Manchester Centre for Genomic Centre for Genetic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; St Mary's Hospital, Manchester Academic Health Science Centre, Manchester, UK
| | - Jacques C Giltay
- Department of Medical Genetics, University Medical Center Utrecht, Utrecht, Netherlands
| | - Dagmar Wieczorek
- Institut für Humangenetik, University of Duisburg-Essen, University Hospital Essen, Essen, Germany
| | - Anna Tostevin
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK
| | - Joanna Wiszniewska
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Sau Wai Cheung
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Raoul C Hennekam
- Department of Pediatrics and Translational Genetics, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Richard A Gibbs
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
| | - Brendan H Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Howard Hughes Medical Institutes, Houston, TX, USA.
| | - Sanjay M Sisodiya
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK; Epilepsy Society, Buckinghamshire, UK.
| |
Collapse
|