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Boßelmann CM, Hedrich UB, Müller P, Sonnenberg L, Parthasarathy S, Helbig I, Lerche H, Pfeifer N. Predicting the functional effects of voltage-gated potassium channel missense variants with multi-task learning. EBioMedicine 2022; 81:104115. [PMID: 35759918 PMCID: PMC9250003 DOI: 10.1016/j.ebiom.2022.104115] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 05/30/2022] [Accepted: 05/31/2022] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Variants in genes encoding voltage-gated potassium channels are associated with a broad spectrum of neurological diseases including epilepsy, ataxia, and intellectual disability. Knowledge of the resulting functional changes, characterized as overall ion channel gain- or loss-of-function, is essential to guide clinical management including precision medicine therapies. However, for an increasing number of variants, little to no experimental data is available. New tools are needed to evaluate variant functional effects. METHODS We catalogued a comprehensive dataset of 959 functional experiments across 19 voltage-gated potassium channels, leveraging data from 782 unique disease-associated and synthetic variants. We used these data to train a taxonomy-based multi-task learning support vector machine (MTL-SVM), and compared performance to several baseline methods. FINDINGS MTL-SVM maintains channel family structure during model training, improving overall predictive performance (mean balanced accuracy 0·718 ± 0·041, AU-ROC 0·761 ± 0·063) over baseline (mean balanced accuracy 0·620 ± 0·045, AU-ROC 0·711 ± 0·022). We can obtain meaningful predictions even for channels with few known variants (KCNC1, KCNQ5). INTERPRETATION Our model enables functional variant prediction for voltage-gated potassium channels. It may assist in tailoring current and future precision therapies for the increasing number of patients with ion channel disorders. FUNDING This work was supported by intramural funding of the Medical Faculty, University of Tuebingen (PATE F.1315137.1), the Federal Ministry for Education and Research (Treat-ION, 01GM1907A/B/G/H) and the German Research Foundation (FOR-2715, Le1030/16-2, He8155/1-2).
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Affiliation(s)
- Christian Malte Boßelmann
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Hoppe-Seyler-Str. 3, D-72076 Tuebingen, Germany,Methods in Medical Informatics, Department of Computer Science, University of Tuebingen, Sand 14, D-72076 Tuebingen, Germany
| | - Ulrike B.S. Hedrich
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Hoppe-Seyler-Str. 3, D-72076 Tuebingen, Germany
| | - Peter Müller
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Hoppe-Seyler-Str. 3, D-72076 Tuebingen, Germany
| | - Lukas Sonnenberg
- Institute for Neurobiology, University of Tuebingen, Tuebingen, Germany
| | - Shridhar Parthasarathy
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA,The Epilepsy NeuroGenetics Initiative (ENGIN), Children's Hospital of Philadelphia, Philadelphia, PA, USA,Department of Biomedical and Health Informatics (DBHi), Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Ingo Helbig
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA,The Epilepsy NeuroGenetics Initiative (ENGIN), Children's Hospital of Philadelphia, Philadelphia, PA, USA,Department of Biomedical and Health Informatics (DBHi), Children's Hospital of Philadelphia, Philadelphia, PA, USA,Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Hoppe-Seyler-Str. 3, D-72076 Tuebingen, Germany,Corresponding authors.
| | - Nico Pfeifer
- Methods in Medical Informatics, Department of Computer Science, University of Tuebingen, Sand 14, D-72076 Tuebingen, Germany,Interfaculty Institute for Biomedical Informatics (IBMI), University of Tuebingen, Tuebingen, Germany,Faculty of Medicine, University of Tuebingen, Tuebingen, Germany,German Center for Infection Research, Partner Site Tuebingen, Tuebingen, Germany,Corresponding authors.
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Helbig KL, Lauerer RJ, Bahr JC, Souza IA, Myers CT, Uysal B, Schwarz N, Gandini MA, Huang S, Keren B, Mignot C, Afenjar A, Billette de Villemeur T, Héron D, Nava C, Valence S, Buratti J, Fagerberg CR, Soerensen KP, Kibaek M, Kamsteeg EJ, Koolen DA, Gunning B, Schelhaas HJ, Kruer MC, Fox J, Bakhtiari S, Jarrar R, Padilla-Lopez S, Lindstrom K, Jin SC, Zeng X, Bilguvar K, Papavasileiou A, Xing Q, Zhu C, Boysen K, Vairo F, Lanpher BC, Klee EW, Tillema JM, Payne ET, Cousin MA, Kruisselbrink TM, Wick MJ, Baker J, Haan E, Smith N, Sadeghpour A, Davis EE, Katsanis N, Corbett MA, MacLennan AH, Gecz J, Biskup S, Goldmann E, Rodan LH, Kichula E, Segal E, Jackson KE, Asamoah A, Dimmock D, McCarrier J, Botto LD, Filloux F, Tvrdik T, Cascino GD, Klingerman S, Neumann C, Wang R, Jacobsen JC, Nolan MA, Snell RG, Lehnert K, Sadleir LG, Anderlid BM, Kvarnung M, Guerrini R, Friez MJ, Lyons MJ, Leonhard J, Kringlen G, Casas K, El Achkar CM, Smith LA, Rotenberg A, Poduri A, Sanchis-Juan A, Carss KJ, Rankin J, Zeman A, Raymond FL, Blyth M, Kerr B, Ruiz K, Urquhart J, Hughes I, Banka S, Hedrich UB, Scheffer IE, Helbig I, Zamponi GW, Lerche H, Mefford HC, Allori A, Angrist M, Ashley P, Bidegain M, Boyd B, Chambers E, Cope H, Cotten CM, Curington T, Davis EE, Ellestad S, Fisher K, French A, Gallentine W, Goldberg R, Hill K, Kansagra S, Katsanis N, Katsanis S, Kurtzberg J, Marcus J, McDonald M, Mikati M, Miller S, Murtha A, Perilla Y, Pizoli C, Purves T, Ross S, Sadeghpour A, Smith E, Wiener J. De Novo Pathogenic Variants in CACNA1E Cause Developmental and Epileptic Encephalopathy with Contractures, Macrocephaly, and Dyskinesias. Am J Hum Genet 2019; 104:562. [PMID: 30849329 DOI: 10.1016/j.ajhg.2019.02.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Helbig KL, Lauerer RJ, Bahr JC, Souza IA, Myers CT, Uysal B, Schwarz N, Gandini MA, Huang S, Keren B, Mignot C, Afenjar A, Billette de Villemeur T, Héron D, Nava C, Valence S, Buratti J, Fagerberg CR, Soerensen KP, Kibaek M, Kamsteeg EJ, Koolen DA, Gunning B, Schelhaas HJ, Kruer MC, Fox J, Bakhtiari S, Jarrar R, Padilla-Lopez S, Lindstrom K, Jin SC, Zeng X, Bilguvar K, Papavasileiou A, Xing Q, Zhu C, Boysen K, Vairo F, Lanpher BC, Klee EW, Tillema JM, Payne ET, Cousin MA, Kruisselbrink TM, Wick MJ, Baker J, Haan E, Smith N, Sadeghpour A, Davis EE, Katsanis N, Corbett MA, MacLennan AH, Gecz J, Biskup S, Goldmann E, Rodan LH, Kichula E, Segal E, Jackson KE, Asamoah A, Dimmock D, McCarrier J, Botto LD, Filloux F, Tvrdik T, Cascino GD, Klingerman S, Neumann C, Wang R, Jacobsen JC, Nolan MA, Snell RG, Lehnert K, Sadleir LG, Anderlid BM, Kvarnung M, Guerrini R, Friez MJ, Lyons MJ, Leonhard J, Kringlen G, Casas K, El Achkar CM, Smith LA, Rotenberg A, Poduri A, Sanchis-Juan A, Carss KJ, Rankin J, Zeman A, Raymond FL, Blyth M, Kerr B, Ruiz K, Urquhart J, Hughes I, Banka S, Hedrich UB, Scheffer IE, Helbig I, Zamponi GW, Lerche H, Mefford HC, Allori A, Angrist M, Ashley P, Bidegain M, Boyd B, Chambers E, Cope H, Cotten CM, Curington T, Davis EE, Ellestad S, Fisher K, French A, Gallentine W, Goldberg R, Hill K, Kansagra S, Katsanis N, Katsanis S, Kurtzberg J, Marcus J, McDonald M, Mikati M, Miller S, Murtha A, Perilla Y, Pizoli C, Purves T, Ross S, Sadeghpour A, Smith E, Wiener J. De Novo Pathogenic Variants in CACNA1E Cause Developmental and Epileptic Encephalopathy with Contractures, Macrocephaly, and Dyskinesias. Am J Hum Genet 2018; 103:666-678. [PMID: 30343943 DOI: 10.1016/j.ajhg.2018.09.006] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 09/17/2018] [Indexed: 12/27/2022] Open
Abstract
Developmental and epileptic encephalopathies (DEEs) are severe neurodevelopmental disorders often beginning in infancy or early childhood that are characterized by intractable seizures, abundant epileptiform activity on EEG, and developmental impairment or regression. CACNA1E is highly expressed in the central nervous system and encodes the α1-subunit of the voltage-gated CaV2.3 channel, which conducts high voltage-activated R-type calcium currents that initiate synaptic transmission. Using next-generation sequencing techniques, we identified de novo CACNA1E variants in 30 individuals with DEE, characterized by refractory infantile-onset seizures, severe hypotonia, and profound developmental impairment, often with congenital contractures, macrocephaly, hyperkinetic movement disorders, and early death. Most of the 14, partially recurring, variants cluster within the cytoplasmic ends of all four S6 segments, which form the presumed CaV2.3 channel activation gate. Functional analysis of several S6 variants revealed consistent gain-of-function effects comprising facilitated voltage-dependent activation and slowed inactivation. Another variant located in the domain II S4-S5 linker results in facilitated activation and increased current density. Five participants achieved seizure freedom on the anti-epileptic drug topiramate, which blocks R-type calcium channels. We establish pathogenic variants in CACNA1E as a cause of DEEs and suggest facilitated R-type calcium currents as a disease mechanism for human epilepsy and developmental disorders.
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Lauxmann S, Verbeek NE, Liu Y, Zaichuk M, Müller S, Lemke JR, van Kempen MJ, Lerche H, Hedrich UB. Relationship of electrophysiological dysfunction and clinical severity in SCN2A
-related epilepsies. Hum Mutat 2018; 39:1942-1956. [DOI: 10.1002/humu.23619] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 07/09/2018] [Accepted: 08/20/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Stephan Lauxmann
- Department of Neurology and Epileptology; Hertie Institute for Clinical Brain Research; University of Tuebingen; Tuebingen Germany
| | - Nienke E. Verbeek
- Department of Genetics; University Medical Centre Utrecht; Utrecht the Netherlands
| | - Yuanyuan Liu
- Department of Neurology and Epileptology; Hertie Institute for Clinical Brain Research; University of Tuebingen; Tuebingen Germany
| | - Mariana Zaichuk
- Department of Neurology and Epileptology; Hertie Institute for Clinical Brain Research; University of Tuebingen; Tuebingen Germany
| | - Stephan Müller
- Department of Neurology and Epileptology; Hertie Institute for Clinical Brain Research; University of Tuebingen; Tuebingen Germany
| | - Johannes R. Lemke
- Institute of Human Genetics; University of Leipzig Hospitals and Clinics; Leipzig Germany
| | | | - Holger Lerche
- Department of Neurology and Epileptology; Hertie Institute for Clinical Brain Research; University of Tuebingen; Tuebingen Germany
| | - Ulrike B.S. Hedrich
- Department of Neurology and Epileptology; Hertie Institute for Clinical Brain Research; University of Tuebingen; Tuebingen Germany
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Syrbe S, Hedrich UB, Riesch E, Djémié T, Müller S, Møller RS, Maher B, Hernandez-Hernandez L, Synofzik M, Caglayan HS, Arslan M, Serratosa JM, Nothnagel M, May P, Krause R, Löffler H, Detert K, Dorn T, Vogt H, Krämer G, Schöls L, Mullis PE, Linnankivi T, Lehesjoki AE, Sterbova K, Craiu DC, Hoffman-Zacharska D, Korff CM, Weber YG, Steinlin M, Gallati S, Bertsche A, Bernhard MK, Merkenschlager A, Kiess W, Gonzalez M, Züchner S, Palotie A, Suls A, De Jonghe P, Helbig I, Biskup S, Wolff M, Maljevic S, Schüle R, Sisodiya SM, Weckhuysen S, Lerche H, Lemke JR. De novo loss- or gain-of-function mutations in KCNA2 cause epileptic encephalopathy. Nat Genet 2015; 47:393-399. [PMID: 25751627 PMCID: PMC4380508 DOI: 10.1038/ng.3239] [Citation(s) in RCA: 188] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 02/06/2015] [Indexed: 02/07/2023]
Abstract
Epileptic encephalopathies are a phenotypically and genetically heterogeneous group of severe epilepsies accompanied by intellectual disability and other neurodevelopmental features. Using next-generation sequencing, we identified four different de novo mutations in KCNA2, encoding the potassium channel KV1.2, in six isolated patients with epileptic encephalopathy (one mutation recurred three times independently). Four individuals presented with febrile and multiple afebrile, often focal seizure types, multifocal epileptiform discharges strongly activated by sleep, mild to moderate intellectual disability, delayed speech development and sometimes ataxia. Functional studies of the two mutations associated with this phenotype showed almost complete loss of function with a dominant-negative effect. Two further individuals presented with a different and more severe epileptic encephalopathy phenotype. They carried mutations inducing a drastic gain-of-function effect leading to permanently open channels. These results establish KCNA2 as a new gene involved in human neurodevelopmental disorders through two different mechanisms, predicting either hyperexcitability or electrical silencing of KV1.2-expressing neurons.
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Affiliation(s)
- Steffen Syrbe
- Department of Women and Child Health, Hospital for Children and Adolescents, University of Leipzig, Leipzig, Germany.
| | - Ulrike B.S. Hedrich
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
| | - Erik Riesch
- Center for Genomics and Transcriptomics (CeGaT) GmbH, Tübingen, Germany.
- Division of Human Genetics, University Children’s Hospital Inselspital, Bern, Switzerland.
- Swiss Epilepsy Center, Zürich, Switzerland.
| | - Tania Djémié
- Neurogenetics group, Department of Molecular Genetics, VIB, Antwerp, Belgium.
- Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.
| | - Stephan Müller
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
| | - Rikke S. Møller
- Danish Epilepsy Center, Dianalund, Denmark
- Institute for Regional Health Services, University of Southern Denmark, Odense, Denmark.
| | - Bridget Maher
- Department of Clinical and Experimental Epilepsy, University College London Institute of Neurology, Queen Square, London, WC1N 3BG, UK
- Epilepsy Society, Chalfont-St-Peter, Bucks, SL9 0RJ, UK.
| | - Laura Hernandez-Hernandez
- Department of Clinical and Experimental Epilepsy, University College London Institute of Neurology, Queen Square, London, WC1N 3BG, UK
- Epilepsy Society, Chalfont-St-Peter, Bucks, SL9 0RJ, UK.
| | - Matthis Synofzik
- Department of Neurodegenerative Diseases, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
- German Research Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | - Hande S. Caglayan
- Department of Molecular Biology and Genetics, Bogazici University, Istanbul, Turkey.
| | - Mutluay Arslan
- Gulhane Military Medical School, Division of Child Neurology, Ankara, Turkey.
| | - José M. Serratosa
- Neurology Lab and Epilepsy Unit, Department of Neurology, IIS — Fundación Jiménez Díaz, UAM, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.
| | - Michael Nothnagel
- Cologne Center for Genomics, University of Colgone, Cologne, Germany
| | - Patrick May
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Roland Krause
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Heidrun Löffler
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
| | - Katja Detert
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
| | | | | | | | - Ludger Schöls
- Department of Neurodegenerative Diseases, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
- German Research Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | - Primus E. Mullis
- Division of Pediatric Endocrinology, University Children’s Hospital Inselspital, Bern, Switzerland.
| | - Tarja Linnankivi
- Pediatric Neurology, Children’s Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
| | - Anna-Elina Lehesjoki
- Folkhälsan Institute of Genetics, Helsinki, Helsinki, Finland.
- Neuroscience Center, University of Helsinki, Helsinki, Finland
- Research Program’s Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
| | - Katalin Sterbova
- Child Neurology Department, 2nd Faculty of Medicine, Charles University, Motol Hospital, Prague, Czech Republic.
| | - Dana C. Craiu
- Pediatric Neurology Clinic II, Department of Neurology, Pediatric Neurology, Psychiatry, and Neurosurgery, “Carol Davila” University of Medicine, Sector 4, Bucharest, Romania.
- Pediatric Neurology Clinic, “Professor Doctor Alexandru Obregia” Clinical Hospital, Sector 4, Bucharest, Romania.
| | | | - Christian M. Korff
- Child and Adolescent Department, Pediatric Neurology, University Hospitals, Geneva, Switzerland.
| | - Yvonne G. Weber
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
| | - Maja Steinlin
- Division of Neuropediatrics, University Children’s Hospital Inselspital, Bern, Switzerland.
| | - Sabina Gallati
- Division of Human Genetics, University Children’s Hospital Inselspital, Bern, Switzerland.
| | - Astrid Bertsche
- Department of Women and Child Health, Hospital for Children and Adolescents, University of Leipzig, Leipzig, Germany.
| | - Matthias K. Bernhard
- Department of Women and Child Health, Hospital for Children and Adolescents, University of Leipzig, Leipzig, Germany.
| | - Andreas Merkenschlager
- Department of Women and Child Health, Hospital for Children and Adolescents, University of Leipzig, Leipzig, Germany.
| | - Wieland Kiess
- Department of Women and Child Health, Hospital for Children and Adolescents, University of Leipzig, Leipzig, Germany.
| | | | - Michael Gonzalez
- Dr. JT MacDonald Department for Human Genetics, Hussman Institute for Human Genomics, University of Miami, Miami, USA
| | - Stephan Züchner
- Dr. JT MacDonald Department for Human Genetics, Hussman Institute for Human Genomics, University of Miami, Miami, USA
| | - Aarno Palotie
- Institute for Molecular Medicine Finland, University of Helsinki, Helsinki, Finland
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, UK.
- Psychiatric & Neurodevelopmental Genetics Unit, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Arvid Suls
- Neurogenetics group, Department of Molecular Genetics, VIB, Antwerp, Belgium.
- Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.
| | - Peter De Jonghe
- Neurogenetics group, Department of Molecular Genetics, VIB, Antwerp, Belgium.
- Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.
- Department of Neurology, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Ingo Helbig
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Germany.
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, USA
| | - Saskia Biskup
- Center for Genomics and Transcriptomics (CeGaT) GmbH, Tübingen, Germany.
| | - Markus Wolff
- Department of Neuropediatrics, University of Tübingen, Tübingen, Germany.
| | - Snezana Maljevic
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
| | - Rebecca Schüle
- Department of Neurodegenerative Diseases, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
- German Research Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
- Division of Neuropediatrics, University Children’s Hospital Inselspital, Bern, Switzerland.
| | - Sanjay M. Sisodiya
- Department of Clinical and Experimental Epilepsy, University College London Institute of Neurology, Queen Square, London, WC1N 3BG, UK
- Epilepsy Society, Chalfont-St-Peter, Bucks, SL9 0RJ, UK.
| | - Sarah Weckhuysen
- Neurogenetics group, Department of Molecular Genetics, VIB, Antwerp, Belgium.
- Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
| | - Johannes R. Lemke
- Department of Women and Child Health, Hospital for Children and Adolescents, University of Leipzig, Leipzig, Germany.
- Division of Human Genetics, University Children’s Hospital Inselspital, Bern, Switzerland.
- Department of Diagnostics, Institute of Human Genetics, University of Leipzig, Leipzig, Germany.
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