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Baynam G, Baker S, Steward C, Summar M, Halley M, Pariser A. Increasing Diversity, Equity, Inclusion, and Accessibility in Rare Disease Clinical Trials. Pharmaceut Med 2024:10.1007/s40290-024-00529-8. [PMID: 38977611 DOI: 10.1007/s40290-024-00529-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/14/2024] [Indexed: 07/10/2024]
Abstract
Diversity, equity, inclusion, and accessibility (DEIA) are foundational principles for clinical trials and medical research. In rare diseases clinical research, where numbers of participants are already challenged by rarity itself, maximizing inclusion is of particular importance to clinical trial success, as well as ensuring the generalizability and relevance of the trial results to the people affected by these diseases. In this article, we review the medical and gray literature and cite case examples to provide insights into how DEIA can be proactively integrated into rare diseases clinical research. Here, we particularly focus on genetic diversity. While the rare diseases DEIA literature is nascent, it is accelerating as many patient advocacy groups, professional societies, training and educational organizations, researcher groups, and funders are setting intentional strategies to attain DEIA goals moving forward, and to establish metrics to ensure continued improvement. Successful examples in underserved and underrepresented populations are available that can serve as case studies upon which rare diseases clinical research programs can be built. Rare diseases have historically been innovation drivers in basic, translational, and clinical research, and ultimately, all populations benefit from data diversity in rare diseases populations that deliver novel insights and approaches to how clinical research can be performed.
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Affiliation(s)
- Gareth Baynam
- Rare Care Centre, Perth Children's Hospital, Perth, WA, Australia
| | - Simeón Baker
- Genomics England, London, UK
- HealthWeb Solutions, London, UK
- School of Health Studies, University of Western Ontario, London, ON, Canada
| | | | | | - Meghan Halley
- Stanford Center for Biomedical Ethics, Stanford University School of Medicine, Stanford, CA, USA
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Dong R, Jin R, Zhang H, Zhang H, Xue M, Li Y, Zhang K, Lv Y, Li X, Liu Y, Gai Z. Genotypic and phenotypic characteristics of sodium channel-associated epilepsy in Chinese population. J Hum Genet 2024:10.1038/s10038-024-01257-2. [PMID: 38880818 DOI: 10.1038/s10038-024-01257-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 04/27/2024] [Accepted: 04/30/2024] [Indexed: 06/18/2024]
Abstract
Variants in voltage-gated sodium channel (VGSC) genes are implicated in seizures, epilepsy, and neurodevelopmental disorders, constituting a significant aspect of hereditary epilepsy in the Chinese population. Through retrospective analysis utilizing next-generation sequencing (NGS), we examined the genotypes and phenotypes of VGSC-related epilepsy cases from a cohort of 691 epilepsy subjects. Our findings revealed that 5.1% of subjects harbored VGSC variants, specifically 22 with SCN1A, 9 with SCN2A, 1 with SCN8A, and 3 with SCN1B variants; no SCN3A variants were detected. Among these, 14 variants were previously reported, while 21 were newly identified. SCN1A variant carriers predominantly presented with Dravet Syndrome (DS) and Genetic Epilepsy with Febrile Seizures Plus (GEFS + ), featuring a heightened sensitivity to fever-induced seizures. Statistically significant disparities emerged between the SCN1A-DS and SCN1A-GEFS+ groups concerning seizure onset and genetic diagnosis age, incidence of status epilepticus, mental retardation, anti-seizure medication (ASM) responsiveness, and familial history. Notably, subjects with SCN1A variants affecting the protein's pore region experienced more frequent cluster seizures. All SCN2A variants were of de novo origin, and 88.9% of individuals with SCN2A variations exhibited cluster seizures. This research reveals a significant association between variations in VGSC-related genes and the clinical phenotype diversity of epilepsy subjects in China, emphasizing the pivotal role of NGS screening in establishing accurate disease diagnoses and guiding the selection of ASM.
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Affiliation(s)
- Rui Dong
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Ruifeng Jin
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
- Department of neurology, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
| | - Hongwei Zhang
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
- Department of neurology, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
| | - Haiyan Zhang
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Min Xue
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Yue Li
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Kaihui Zhang
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Yuqiang Lv
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Xiaoying Li
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China.
- Neonatology department, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China.
| | - Yi Liu
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China.
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China.
| | - Zhongtao Gai
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
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Sampedro-Castañeda M, Baltussen LL, Lopes AT, Qiu Y, Sirvio L, Mihaylov SR, Claxton S, Richardson JC, Lignani G, Ultanir SK. Epilepsy-linked kinase CDKL5 phosphorylates voltage-gated calcium channel Cav2.3, altering inactivation kinetics and neuronal excitability. Nat Commun 2023; 14:7830. [PMID: 38081835 PMCID: PMC10713615 DOI: 10.1038/s41467-023-43475-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 11/09/2023] [Indexed: 12/18/2023] Open
Abstract
Developmental and epileptic encephalopathies (DEEs) are a group of rare childhood disorders characterized by severe epilepsy and cognitive deficits. Numerous DEE genes have been discovered thanks to advances in genomic diagnosis, yet putative molecular links between these disorders are unknown. CDKL5 deficiency disorder (CDD, DEE2), one of the most common genetic epilepsies, is caused by loss-of-function mutations in the brain-enriched kinase CDKL5. To elucidate CDKL5 function, we looked for CDKL5 substrates using a SILAC-based phosphoproteomic screen. We identified the voltage-gated Ca2+ channel Cav2.3 (encoded by CACNA1E) as a physiological target of CDKL5 in mice and humans. Recombinant channel electrophysiology and interdisciplinary characterization of Cav2.3 phosphomutant mice revealed that loss of Cav2.3 phosphorylation leads to channel gain-of-function via slower inactivation and enhanced cholinergic stimulation, resulting in increased neuronal excitability. Our results thus show that CDD is partly a channelopathy. The properties of unphosphorylated Cav2.3 closely resemble those described for CACNA1E gain-of-function mutations causing DEE69, a disorder sharing clinical features with CDD. We show that these two single-gene diseases are mechanistically related and could be ameliorated with Cav2.3 inhibitors.
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Affiliation(s)
| | - Lucas L Baltussen
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
- Laboratory for the Research of Neurodegenerative Diseases (VIB-KU Leuven), Department of Neurosciences, ON5 Herestraat 49, 3000, Leuven, Belgium
| | - André T Lopes
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Yichen Qiu
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square House, London, WC1N 3BG, UK
| | - Liina Sirvio
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Simeon R Mihaylov
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Suzanne Claxton
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Jill C Richardson
- Neuroscience, MSD Research Laboratories, 120 Moorgate, London, EC2M 6UR, UK
| | - Gabriele Lignani
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square House, London, WC1N 3BG, UK
| | - Sila K Ultanir
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.
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Afsar T, Huang X, Shah AA, Abbas S, Bano S, Mahmood A, Hu J, Razak S, Umair M. Truncated DNM1 variant underlines developmental delay and epileptic encephalopathy. Front Pediatr 2023; 11:1266376. [PMID: 37900685 PMCID: PMC10601988 DOI: 10.3389/fped.2023.1266376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 09/06/2023] [Indexed: 10/31/2023] Open
Abstract
Background Developmental and epileptic encephalopathies (DEEs) signify a group of heterogeneous neurodevelopmental disorder associated with early-onset seizures accompanied by developmental delay, hypotonia, mild to severe intellectual disability, and developmental regression. Variants in the DNM1 gene have been associated with autosomal dominant DEE type 31A and autosomal recessive DEE type 31B. Methods In the current study, a consanguineous Pakistani family consisting of a proband (IV-2) was clinically evaluated and genetically analyzed manifesting in severe neurodevelopmental phenotypes. WES followed by Sanger sequencing was performed to identify the disease-causing variant. Furthermore, 3D protein modeling and dynamic simulation of wild-type and mutant proteins along with reverse transcriptase (RT)-based mRNA expression were checked using standard methods. Results Data analysis of WES revealed a novel homozygous non-sense variant (c.1402G>T; p. Glu468*) in exon 11 of the DNM1 gene that was predicted as pathogenic class I. Variants in the DNM1 gene have been associated with DEE types 31A and B. Different bioinformatics prediction tools and American College of Medical Genetics guidelines were used to verify the identified variant. Sanger sequencing was used to validate the disease-causing variant. Our approach validated the pathogenesis of the variant as a cause of heterogeneous neurodevelopmental disorders. In addition, 3D protein modeling showed that the mutant protein would lose most of the amino acids and might not perform the proper function if the surveillance non-sense-mediated decay mechanism was skipped. Molecular dynamics analysis showed varied trajectories of wild-type and mutant DNM1 proteins in terms of root mean square deviation, root mean square fluctuation and radius of gyration. Similarly, RT-qPCR revealed a substantial reduction of the DNM1 gene in the index patient. Conclusion Our finding further confirms the association of homozygous, loss-of-function variants in DNM1 associated with DEE type 31B. The study expands the genotypic and phenotypic spectrum of pathogenic DNM1 variants related to DNM1-associated pathogenesis.
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Affiliation(s)
- Tayyaba Afsar
- Department of Community Health Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
- King Salman Center for Disability Research, Riyadh, Saudi Arabia
| | - Xiaoyun Huang
- Department of Neurology, SSL Central Hospital of Dongguan City, Affiliated Dongguan Shilong People’s Hospital of Southern Medical University, Dongguan, China
| | - Abid Ali Shah
- Center for Medical Genetics and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, China
| | - Safdar Abbas
- Department of Biological Sciences, Dartmouth College, Hanover, NH, United States
| | - Shazia Bano
- Department of Optometry and Vision Sciences, University of Lahore, Lahore, Pakistan
| | - Arif Mahmood
- Department of Neurology, SSL Central Hospital of Dongguan City, Affiliated Dongguan Shilong People’s Hospital of Southern Medical University, Dongguan, China
| | - Junjian Hu
- Department of Central Laboratory, SSL Central Hospital of Dongguan City, Affiliated Dongguan Shilong People’s Hospital of Southern Medical University, Dongguan, China
| | - Suhail Razak
- Department of Community Health Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
- King Salman Center for Disability Research, Riyadh, Saudi Arabia
| | - Muhammad Umair
- King Salman Center for Disability Research, Riyadh, Saudi Arabia
- Medical Genomics Research Department, King Abdullah International Medical Research Center (KAIMRC), King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs (MNGH), Riyadh, Saudi Arabia
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Amaral P, Carbonell-Sala S, De La Vega FM, Faial T, Frankish A, Gingeras T, Guigo R, Harrow JL, Hatzigeorgiou AG, Johnson R, Murphy TD, Pertea M, Pruitt KD, Pujar S, Takahashi H, Ulitsky I, Varabyou A, Wells CA, Yandell M, Carninci P, Salzberg SL. The status of the human gene catalogue. Nature 2023; 622:41-47. [PMID: 37794265 PMCID: PMC10575709 DOI: 10.1038/s41586-023-06490-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 07/27/2023] [Indexed: 10/06/2023]
Abstract
Scientists have been trying to identify every gene in the human genome since the initial draft was published in 2001. In the years since, much progress has been made in identifying protein-coding genes, currently estimated to number fewer than 20,000, with an ever-expanding number of distinct protein-coding isoforms. Here we review the status of the human gene catalogue and the efforts to complete it in recent years. Beside the ongoing annotation of protein-coding genes, their isoforms and pseudogenes, the invention of high-throughput RNA sequencing and other technological breakthroughs have led to a rapid growth in the number of reported non-coding RNA genes. For most of these non-coding RNAs, the functional relevance is currently unclear; we look at recent advances that offer paths forward to identifying their functions and towards eventually completing the human gene catalogue. Finally, we examine the need for a universal annotation standard that includes all medically significant genes and maintains their relationships with different reference genomes for the use of the human gene catalogue in clinical settings.
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Affiliation(s)
- Paulo Amaral
- INSPER Institute of Education and Research, Sao Paulo, Brazil
| | | | - Francisco M De La Vega
- Department of Biomedical Data Science, Stanford University School of Medicine, Stanford, CA, USA
- Tempus Labs, Chicago, IL, USA
| | | | - Adam Frankish
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, UK
| | - Thomas Gingeras
- Department of Functional Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Roderic Guigo
- Centre for Genomic Regulation (CRG), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Jennifer L Harrow
- Centre for Genomics Research, Discovery Sciences, AstraZeneca, Royston, UK
| | - Artemis G Hatzigeorgiou
- Department of Computer Science and Biomedical Informatics, Universithy of Thessaly, Lamia, Greece
- Hellenic Pasteur Institute, Athens, Greece
| | - Rory Johnson
- School of Biology and Environmental Science, University College Dublin, Dublin, Ireland
- Conway Institute of Biomedical and Biomolecular Research, University College Dublin, Dublin, Ireland
- Department of Medical Oncology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Department for BioMedical Research, University of Bern, Bern, Switzerland
| | - Terence D Murphy
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Mihaela Pertea
- Center for Computational Biology, Johns Hopkins University, Baltimore, MD, USA
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, USA
| | - Kim D Pruitt
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Shashikant Pujar
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Hazuki Takahashi
- Laboratory for Transcriptome Technology, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Igor Ulitsky
- Department of Immunology and Regenerative Biology, Weizmann Institute of Science, Rehovot, Israel
- Department of Molecular Neuroscience, Weizmann Institute of Science, Rehovot, Israel
| | - Ales Varabyou
- Center for Computational Biology, Johns Hopkins University, Baltimore, MD, USA
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, USA
| | - Christine A Wells
- Stem Cell Systems, Department of Anatomy and Physiology, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Mark Yandell
- Departent of Human Genetics, Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT, USA
| | - Piero Carninci
- Laboratory for Transcriptome Technology, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan.
- Human Technopole, Milan, Italy.
| | - Steven L Salzberg
- Center for Computational Biology, Johns Hopkins University, Baltimore, MD, USA.
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA.
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, USA.
- Department of Biostatistics, Johns Hopkins University, Baltimore, MD, USA.
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6
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Sills GJ. Pharmacological diversity amongst approved and emerging antiseizure medications for the treatment of developmental and epileptic encephalopathies. Ther Adv Neurol Disord 2023; 16:17562864231191000. [PMID: 37655228 PMCID: PMC10467199 DOI: 10.1177/17562864231191000] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 07/13/2023] [Indexed: 09/02/2023] Open
Abstract
Developmental and epileptic encephalopathies (DEEs) are rare neurodevelopmental disorders characterised by early-onset and often intractable seizures and developmental delay/regression, and include Dravet syndrome and Lennox-Gastaut syndrome (LGS). Rufinamide, fenfluramine, stiripentol, cannabidiol and ganaxolone are antiseizure medications (ASMs) with diverse mechanisms of action that have been approved for treating specific DEEs. Rufinamide is thought to suppress neuronal hyperexcitability by preventing the functional recycling of voltage-gated sodium channels from the inactivated to resting state. It is licensed for adjunctive treatment of seizures associated with LGS. Fenfluramine increases extracellular serotonin levels and may reduce seizures via activation of specific serotonin receptors and positive modulation of the sigma-1 receptor. Fenfluramine is licensed for adjunctive treatment of seizures associated with Dravet syndrome and LGS. Stiripentol is a positive allosteric modulator of type-A gamma-aminobutyric acid (GABAA) receptors. As a broad-spectrum inhibitor of cytochrome P450 enzymes, its antiseizure effects may additionally arise through pharmacokinetic interactions with co-administered ASMs. Stiripentol is licensed for treating seizures associated with Dravet syndrome in patients taking clobazam and/or valproate. The mechanism(s) of action of cannabidiol remains largely unclear although multiple targets have been proposed, including transient receptor potential vanilloid 1, G protein-coupled receptor 55 and equilibrative nucleoside transporter 1. Cannabidiol is licensed as adjunctive treatment in conjunction with clobazam for seizures associated with Dravet syndrome and LGS, and as adjunctive treatment of seizures associated with tuberous sclerosis complex. Like stiripentol, ganaxolone is a positive allosteric modulator at GABAA receptors. It has recently been licensed in the USA for the treatment of seizures associated with cyclin-dependent kinase-like 5 deficiency disorder. Greater understanding of the causes of DEEs has driven research into the potential use of other novel and repurposed agents. Putative ASMs currently in clinical development for use in DEEs include soticlestat, carisbamate, verapamil, radiprodil, clemizole and lorcaserin.
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Affiliation(s)
- Graeme J. Sills
- School of Life Sciences, University of Glasgow, Room 341, Sir James Black Building, Glasgow G12 8QQ, UK
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Sparber P, Bychkov I, Pyankov D, Skoblov M. Functional investigation of SCN1A deep-intronic variants activating poison exons inclusion. Hum Genet 2023; 142:1043-1053. [PMID: 37186029 DOI: 10.1007/s00439-023-02564-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 04/19/2023] [Indexed: 05/17/2023]
Abstract
Dravet syndrome is a devastating epileptic syndrome characterized by intractable epilepsy with an early age of onset, regression of developmental milestones, ataxia, and motor deficits. Loss-of-function pathogenic variants in the SCN1A gene are found in the majority of patients with Dravet syndrome; however, a significant number of patients remain undiagnosed even after comprehensive genetic testing. Previously, it was shown that intronic elements in the SCN1A gene called poison exons can incorporate into SCN1A mRNA, leading to haploinsufficiency and potentially causing Dravet syndrome. Here, we developed a splicing reporter assay for all described poison exons of the SCN1A gene and validated it using previously reported and artificially introduced variants. Overall, we tested 18 deep-intronic single nucleotide variants and one complex allele in the SCN1A gene. Our approach is capable of evaluating the effect of both variants affecting cis-regulatory sequences and splice-site variants, with the potential to functionally annotate every possible variant within these elements. Moreover, using antisense-modified uridine-rich U7 small nuclear RNAs, we were able to block poison exon incorporation in mutant constructs, an approach that could be used as a promising therapeutic intervention in Dravet syndrome patients with deep-intronic variants.
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Affiliation(s)
- Peter Sparber
- Laboratory of Functional Genomics, Research Centre for Medical Genetics, Moskvorechie Street 1, Moscow, Russia, 115478.
| | - Igor Bychkov
- Laboratory of Hereditary Metabolic Diseases, Research Centre for Medical Genetics, Moscow, Russia
| | | | - Mikhail Skoblov
- Laboratory of Functional Genomics, Research Centre for Medical Genetics, Moskvorechie Street 1, Moscow, Russia, 115478
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8
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Felker SA, Lawlor JMJ, Hiatt SM, Thompson ML, Latner DR, Finnila CR, Bowling KM, Bonnstetter ZT, Bonini KE, Kelly NR, Kelley WV, Hurst ACE, Rashid S, Kelly MA, Nakouzi G, Hendon LG, Bebin EM, Kenny EE, Cooper GM. Poison exon annotations improve the yield of clinically relevant variants in genomic diagnostic testing. Genet Med 2023; 25:100884. [PMID: 37161864 PMCID: PMC10524927 DOI: 10.1016/j.gim.2023.100884] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 05/01/2023] [Accepted: 05/03/2023] [Indexed: 05/11/2023] Open
Abstract
PURPOSE Neurodevelopmental disorders (NDDs) often result from rare genetic variation, but genomic testing yield for NDDs remains below 50%, suggesting that clinically relevant variants may be missed by standard analyses. Here, we analyze "poison exons" (PEs), which are evolutionarily conserved alternative exons often absent from standard gene annotations. Variants that alter PE inclusion can lead to loss of function and may be highly penetrant contributors to disease. METHODS We curated published RNA sequencing data from developing mouse cortex to define 1937 conserved PE regions potentially relevant to NDDs, and we analyzed variants found by genome sequencing in multiple NDD cohorts. RESULTS Across 2999 probands, we found 6 novel clinically relevant variants in PE regions. Five of these variants are in genes that are part of the sodium voltage-gated channel alpha subunit family (SCN1A, SCN2A, and SCN8A), which is associated with epilepsies. One variant is in SNRPB, associated with cerebrocostomandibular syndrome. These variants have moderate to high computational impact assessments, are absent from population variant databases, and in genes with gene-phenotype associations consistent with each probands reported features. CONCLUSION With a very minimal increase in variant analysis burden (average of 0.77 variants per proband), annotation of PEs can improve diagnostic yield for NDDs and likely other congenital conditions.
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Affiliation(s)
| | | | - Susan M Hiatt
- HudsonAlpha Institute for Biotechnology, Huntsville, AL
| | | | | | | | | | | | - Katherine E Bonini
- Institute for Genomic Health, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Nicole R Kelly
- Division of Pediatric Genetic Medicine, Department of Pediatrics, Children's Hospital at Montefiore/Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY
| | | | | | | | | | | | | | - E Martina Bebin
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL
| | - Eimear E Kenny
- Institute for Genomic Health, Icahn School of Medicine at Mount Sinai, New York, NY; Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY; Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY
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9
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Amaral P, Carbonell-Sala S, De La Vega FM, Faial T, Frankish A, Gingeras T, Guigo R, Harrow JL, Hatzigeorgiou AG, Johnson R, Murphy TD, Pertea M, Pruitt KD, Pujar S, Takahashi H, Ulitsky I, Varabyou A, Wells CA, Yandell M, Carninci P, Salzberg SL. The status of the human gene catalogue. ARXIV 2023:arXiv:2303.13996v1. [PMID: 36994150 PMCID: PMC10055485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Scientists have been trying to identify all of the genes in the human genome since the initial draft of the genome was published in 2001. Over the intervening years, much progress has been made in identifying protein-coding genes, and the estimated number has shrunk to fewer than 20,000, although the number of distinct protein-coding isoforms has expanded dramatically. The invention of high-throughput RNA sequencing and other technological breakthroughs have led to an explosion in the number of reported non-coding RNA genes, although most of them do not yet have any known function. A combination of recent advances offers a path forward to identifying these functions and towards eventually completing the human gene catalogue. However, much work remains to be done before we have a universal annotation standard that includes all medically significant genes, maintains their relationships with different reference genomes, and describes clinically relevant genetic variants.
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Affiliation(s)
- Paulo Amaral
- INSPER Institute of Education and Research, São Paulo, SP, Brasil
| | - Silvia Carbonell-Sala
- Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003, Barcelona, Catalonia, Spain
| | - Francisco M. De La Vega
- Department of Biomedical Data Science, Stanford University School of Medicine, Stanford, CA; Tempus Labs, Inc., Chicago, IL
| | | | - Adam Frankish
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Thomas Gingeras
- Department of Functional Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY
| | - Roderic Guigo
- Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003, Barcelona, Catalonia, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Catalonia, Spain
| | - Jennifer L Harrow
- Centre for Genomics Research, Discovery Sciences, AstraZeneca, Da Vinci Building. Melbourn Science Park, Royston UK SG8 6HB
| | - Artemis G. Hatzigeorgiou
- Universithy of Thessaly, Department of Computer Science and Biomedical Informatics, Lamia, Greece; Hellenic Pasteur Institute, Athens, Greece
| | - Rory Johnson
- School of Biology and Environmental Science, University College Dublin, D04 V1W8 Dublin, Ireland; Conway Institute of Biomedical and Biomolecular Research, University College Dublin, D04 V1W8 Dublin, Ireland; Department of Medical Oncology, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland; Department for BioMedical Research, University of Bern, 3008 Bern, Switzerland
| | - Terence D. Murphy
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Mihaela Pertea
- Center for Computational Biology, Johns Hopkins University, Baltimore, MD, USA
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Kim D. Pruitt
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Shashikant Pujar
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Hazuki Takahashi
- Laboratory for Transcriptome Technology, RIKEN Center for Integrative Medical Sciences, Yokohama Kanagawa 230-0045 Japan
| | - Igor Ulitsky
- Department of Immunology and Regenerative Biology; Department of Molecular Neuroscience, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ales Varabyou
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, USA
| | - Christine A. Wells
- Stem Cell Systems, Department of Anatomy and Physiology, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville 3010 Vic Australia
| | - Mark Yandell
- Departent of Human Genetics, Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT, USA
| | - Piero Carninci
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
- Human Technopole, via Rita Levi Montalcini 1, Milan 20157 Italy
| | - Steven L. Salzberg
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
- Center for Computational Biology, Johns Hopkins University, Baltimore, MD, USA
- Department of Immunology and Regenerative Biology; Department of Molecular Neuroscience, Weizmann Institute of Science, Rehovot 76100, Israel
- Department of Biostatistics, Johns Hopkins University, Baltimore, MD, USA
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10
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Felker SA, Lawlor JMJ, Hiatt SM, Thompson ML, Latner DR, Finnila CR, Bowling KM, Bonnstetter ZT, Bonini KE, Kelly NR, Kelley WV, Hurst ACE, Kelly MA, Nakouzi G, Hendon LG, Bebin EM, Kenny EE, Cooper GM. Poison exon annotations improve the yield of clinically relevant variants in genomic diagnostic testing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.12.523654. [PMID: 36711854 PMCID: PMC9882217 DOI: 10.1101/2023.01.12.523654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Purpose Neurodevelopmental disorders (NDDs) often result from rare genetic variation, but genomic testing yield for NDDs remains around 50%, suggesting some clinically relevant rare variants may be missed by standard analyses. Here we analyze "poison exons" (PEs) which, while often absent from standard gene annotations, are alternative exons whose inclusion results in a premature termination codon. Variants that alter PE inclusion can lead to loss-of-function and may be highly penetrant contributors to disease. Methods We curated published RNA-seq data from developing mouse cortex to define 1,937 PE regions conserved between humans and mice and potentially relevant to NDDs. We then analyzed variants found by genome sequencing in multiple NDD cohorts. Results Across 2,999 probands, we found six clinically relevant variants in PE regions that were previously overlooked. Five of these variants are in genes that are part of the sodium voltage-gated channel alpha subunit family ( SCN1A, SCN2A , and SCN8A ), associated with epilepsies. One variant is in SNRPB , associated with Cerebrocostomandibular Syndrome. These variants have moderate to high computational impact assessments, are absent from population variant databases, and were observed in probands with features consistent with those reported for the associated gene. Conclusion With only a minimal increase in variant analysis burden (most probands had zero or one candidate PE variants in a known NDD gene, with an average of 0.77 per proband), annotation of PEs can improve diagnostic yield for NDDs and likely other congenital conditions.
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Affiliation(s)
| | - James MJ Lawlor
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA 35806
| | - Susan M Hiatt
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA 35806
| | | | - Donald R Latner
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA 35806
| | | | - Kevin M Bowling
- Washington University School of Medicine, Saint Louis, MO, USA 63110
| | | | - Katherine E Bonini
- Institute for Genomic Health, Icahn School of Medicine at Mount Sinai. New York, NY, USA 10029
| | - Nicole R Kelly
- Department of Pediatrics, Division of Pediatric Genetic Medicine, Children’s Hospital at Montefiore/Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY, USA 10467
| | - Whitley V Kelley
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA 35806
| | - Anna CE Hurst
- University of Alabama in Birmingham, Birmingham, AL, USA 35294
| | | | | | - Laura G Hendon
- University of Mississippi Medical Center, Jackson, MS, 39216
| | - E Martina Bebin
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA 35294
| | - Eimear E Kenny
- Institute for Genomic Health, Icahn School of Medicine at Mount Sinai. New York, NY, USA 10029,Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA 10029,Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA 10029
| | - Gregory M Cooper
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA 35806
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11
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Cormier MJ, Pedersen BS, Bayrak-Toydemir P, Quinlan AR. Combining genetic constraint with predictions of alternative splicing to prioritize deleterious splicing in rare disease studies. BMC Bioinformatics 2022; 23:482. [PMCID: PMC9664736 DOI: 10.1186/s12859-022-05041-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 11/07/2022] [Indexed: 11/16/2022] Open
Abstract
Abstract
Background
Despite numerous molecular and computational advances, roughly half of patients with a rare disease remain undiagnosed after exome or genome sequencing. A particularly challenging barrier to diagnosis is identifying variants that cause deleterious alternative splicing at intronic or exonic loci outside of canonical donor or acceptor splice sites.
Results
Several existing tools predict the likelihood that a genetic variant causes alternative splicing. We sought to extend such methods by developing a new metric that aids in discerning whether a genetic variant leads to deleterious alternative splicing. Our metric combines genetic variation in the Genome Aggregate Database with alternative splicing predictions from SpliceAI to compare observed and expected levels of splice-altering genetic variation. We infer genic regions with significantly less splice-altering variation than expected to be constrained. The resulting model of regional splicing constraint captures differential splicing constraint across gene and exon categories, and the most constrained genic regions are enriched for pathogenic splice-altering variants. Building from this model, we developed ConSpliceML. This ensemble machine learning approach combines regional splicing constraint with multiple per-nucleotide alternative splicing scores to guide the prediction of deleterious splicing variants in protein-coding genes. ConSpliceML more accurately distinguishes deleterious and benign splicing variants than state-of-the-art splicing prediction methods, especially in “cryptic” splicing regions beyond canonical donor or acceptor splice sites.
Conclusion
Integrating a model of genetic constraint with annotations from existing alternative splicing tools allows ConSpliceML to prioritize potentially deleterious splice-altering variants in studies of rare human diseases.
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12
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Lin JJ, Meletti S, Vaudano AE, Lin KL. Developmental and epileptic encephalopathies: Is prognosis related to different epileptic network dysfunctions? Epilepsy Behav 2022; 131:107654. [PMID: 33349540 DOI: 10.1016/j.yebeh.2020.107654] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/17/2020] [Accepted: 11/18/2020] [Indexed: 11/19/2022]
Abstract
Developmental and epileptic encephalopathies are a group of rare, severe epilepsies, which are characterized by refractory seizures starting in infancy or childhood and developmental delay or regression. Developmental changes might be independent of epilepsy. However, interictal epileptic activity and seizures can further deteriorate cognition and behavior. Recently, the concept of developmental and epileptic encephalopathies has moved from the lesions associated with epileptic encephalopathies toward the epileptic network dysfunctions on the functioning of the brain. Early recognition and differentiation of patients with developmental and epileptic encephalopathies is important, as precision therapies need to be holistic to address the often devastating symptoms. In this review, we discuss the evolution of the concept of developmental and epileptic encephalopathies in recent years, as well as the current understanding of the genetic basis of developmental and epileptic encephalopathies. Finally, we will discuss the role of epileptic network dysfunctions on prognosis for these severe conditions.
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Affiliation(s)
- Jainn-Jim Lin
- Division of Pediatric Critical Care and Pediatric Neurocritical Care Center, Chang Gung Children's Hospital and Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan; Graduate Institute of Clinical Medical Sciences, Chang Gung University, College of Medicine, Taoyuan, Taiwan; Division of Pediatric Neurology, Chang Gung Children's Hospital and Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan; Department of Respiratory Therapy, Chang Gung Children's Hospital and Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan; Study Group for Intensive and Integrated Care of Pediatric Central Nervous System (iCNS Group), Chang Gung Children's Hospital, Taoyuan, Taiwan
| | - Stefano Meletti
- Division of Neurology, University Hospital of Modena, Modena, Italy; Department of Biomedical, Metabolic and Neural Science, University of Modena and Reggio Emilia, Modena, Italy
| | - Anna Elisabetta Vaudano
- Division of Neurology, University Hospital of Modena, Modena, Italy; Department of Biomedical, Metabolic and Neural Science, University of Modena and Reggio Emilia, Modena, Italy
| | - Kuang-Lin Lin
- Division of Pediatric Neurology, Chang Gung Children's Hospital and Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan; Study Group for Intensive and Integrated Care of Pediatric Central Nervous System (iCNS Group), Chang Gung Children's Hospital, Taoyuan, Taiwan.
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13
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Dzinovic I, Škorvánek M, Necpál J, Boesch S, Švantnerová J, Wagner M, Havránková P, Pavelekova P, Haň V, Janzarik WG, Berweck S, Diebold I, Kuster A, Jech R, Winkelmann J, Zech M. Dystonia as a prominent presenting feature in developmental and epileptic encephalopathies: A case series. Parkinsonism Relat Disord 2021; 90:73-78. [PMID: 34399161 DOI: 10.1016/j.parkreldis.2021.08.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 08/03/2021] [Accepted: 08/06/2021] [Indexed: 01/04/2023]
Abstract
INTRODUCTION Although there has been increasing recognition of the occurrence of non-epileptic involuntary movements in developmental and epileptic encephalopathies (DEEs), the spectrum of dystonic presentations associated with these conditions remains poorly described. We sought to expand the catalogue of dystonia-predominant phenotypes in monogenic DEEs, building on the recently introduced concept of an epilepsy-movement disorder spectrum. METHODS Cases were identified from a whole-exome-sequenced cohort of 45 pediatric index patients with complex dystonia (67% sequenced as parent-child trios). Review of molecular findings in DEE-associated genes was performed. For five individuals with identified DEE-causing variants, detailed information about presenting phenotypic features and the natural history of disease was obtained. RESULTS De-novo pathogenic and likely pathogenic missense variants in GABRA1, GABBR2, GNAO1, and FOXG1 gave rise to infantile-onset persistent and paroxysmal dystonic manifestations, beginning in the limb or truncal musculature and progressing gradually to a generalized state. Coexisting, less prominent movement-disorder symptoms were observed and included myoclonic, ballistic, and stereotypic abnormal movements as well as choreoathetosis. Dystonia dominated over epileptic neurodevelopmental comorbidities in all four subjects and represented the primary indication for molecular genetic analysis. We also report the unusual case of an adult female patient with dystonia, tremor, and mild learning disability who was found to harbor a pathogenic frameshift variant in MECP2. CONCLUSIONS Dystonia can be a leading clinical manifestation in different DEEs. A monogenic basis of disease should be considered on the association of dystonia and developmental delay-epilepsy presentations, justifying a molecular screening for variants in DEE-associated genes.
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Affiliation(s)
- Ivana Dzinovic
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany
| | - Matej Škorvánek
- Department of Neurology, P.J. Safarik University, Kosice, Slovak Republic; Department of Neurology, University Hospital of L. Pasteur, Kosice, Slovak Republic
| | - Ján Necpál
- Department of Neurology, Zvolen Hospital, Slovakia
| | - Sylvia Boesch
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | - Jana Švantnerová
- Second Department of Neurology, Faculty of Medicine, Comenius University, University Hospital Bratislava, Bratislava, Slovakia
| | - Matias Wagner
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany; Technical University of Munich, Munich, Germany; School of Medicine, Institute of Human Genetics
| | - Petra Havránková
- Department of Neurology, Charles University, 1st Faculty of Medicine and General University Hospital in Prague, Prague, Czech Republic
| | - Petra Pavelekova
- Department of Neurology, P.J. Safarik University, Kosice, Slovak Republic; Department of Neurology, University Hospital of L. Pasteur, Kosice, Slovak Republic
| | - Vladimír Haň
- Department of Neurology, P.J. Safarik University, Kosice, Slovak Republic; Department of Neurology, University Hospital of L. Pasteur, Kosice, Slovak Republic
| | - Wibke G Janzarik
- Department of Neuropediatrics and Muscle Disorders, University Medical Center, Faculty of Medicine, University of Freiburg, Germany
| | - Steffen Berweck
- Ludwig Maximilian University of Munich, Munich, Germany; Hospital for Neuropediatrics and Neurological Rehabilitation, Centre of Epilepsy for Children and Adolescents, Schoen Klinik Vogtareuth, Vogtareuth, Germany
| | - Isabel Diebold
- MGZ - Medical Genetics Center Munich, Munich, Germany; Department of Pediatrics, Technical University of Munich School of Medicine, Munich, Germany
| | - Alice Kuster
- Inborn Errors of Metabolism, Pediatric Intensive Care Unit, University Hospital of Nantes, Nantes, France
| | - Robert Jech
- Department of Neurology, Charles University, 1st Faculty of Medicine and General University Hospital in Prague, Prague, Czech Republic
| | - Juliane Winkelmann
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany; Technical University of Munich, Munich, Germany; School of Medicine, Institute of Human Genetics; Lehrstuhl für Neurogenetik, Technische Universität München, Munich, Germany; Munich Cluster for Systems Neurology, SyNergy, Munich, Germany
| | - Michael Zech
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany; Technical University of Munich, Munich, Germany; School of Medicine, Institute of Human Genetics.
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14
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Yigit G, Sheffer R, Daana M, Li Y, Kaygusuz E, Mor-Shakad H, Altmüller J, Nürnberg P, Douiev L, Kaulfuss S, Burfeind P, Wollnik B, Brockmann K. Loss-of-function variants in DNM1 cause a specific form of developmental and epileptic encephalopathy only in biallelic state. J Med Genet 2021; 59:549-553. [PMID: 34172529 PMCID: PMC9132866 DOI: 10.1136/jmedgenet-2021-107769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 05/08/2021] [Indexed: 11/23/2022]
Abstract
Background Developmental and epileptic encephalopathies (DEEs) represent a group of severe neurological disorders characterised by an onset of refractory seizures during infancy or early childhood accompanied by psychomotor developmental delay or regression. DEEs are genetically heterogeneous with, to date, more than 80 different genetic subtypes including DEE31 caused by heterozygous missense variants in DNM1. Methods We performed a detailed clinical characterisation of two unrelated patients with DEE and used whole-exome sequencing to identify causative variants in these individuals. The identified variants were tested for cosegregation in the respective families. Results We excluded pathogenic variants in known, DEE-associated genes. We identified homozygous nonsense variants, c.97C>T; p.(Gln33*) in family 1 and c.850C>T; p.(Gln284*) in family 2, in the DNM1 gene, indicating that biallelic, loss-of-function pathogenic variants in DNM1 cause DEE. Conclusion Our finding that homozygous, loss-of-function variants in DNM1 cause DEE expands the spectrum of pathogenic variants in DNM1. All parents who were heterozygous carriers of the identified loss-of-function variants were healthy and did not show any clinical symptoms, indicating that the type of mutation in DNM1 determines the pattern of inheritance.
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Affiliation(s)
- Gökhan Yigit
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany
| | - Ruth Sheffer
- Department of Human Genetics, Hadassah University Hospital, Jerusalem, Israel
| | - Muhannad Daana
- Child Development Institute, Clalit Health Services, Tel Aviv, Israel
| | - Yun Li
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany
| | - Emrah Kaygusuz
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany.,Molecular Biology and Genetics, Bilecik Şeyh Edebali University, Bilecik, Turkey
| | - Hagar Mor-Shakad
- Department of Human Genetics, Hadassah University Hospital, Jerusalem, Israel
| | - Janine Altmüller
- Cologne Center for Genomics (CCG), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Peter Nürnberg
- Cologne Center for Genomics (CCG), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Liza Douiev
- Department of Human Genetics, Hadassah University Hospital, Jerusalem, Israel
| | - Silke Kaulfuss
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany
| | - Peter Burfeind
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany
| | - Bernd Wollnik
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany .,Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Gottingen, Gottingen, Germany
| | - Knut Brockmann
- Interdisciplinary Pediatric Center for Children with Developmental Disabilities and Severe Chronic Disorders, University Medical Center Göttingen, Gottingen, Germany
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15
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Aziz MC, Schneider PN, Carvill GL. Targeting Poison Exons to Treat Developmental and Epileptic Encephalopathy. Dev Neurosci 2021; 43:241-246. [PMID: 33971653 DOI: 10.1159/000516143] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 03/16/2021] [Indexed: 11/19/2022] Open
Abstract
Developmental and epileptic encephalopathies (DEEs) describe a subset of neurodevelopmental disorders categorized by refractory epilepsy that is often associated with intellectual disability and autism spectrum disorder. The majority of DEEs are now known to have a genetic basis with de novo coding variants accounting for the majority of cases. More recently, a small number of individuals have been identified with intronic SCN1A variants that result in alternative splicing events that lead to ectopic inclusion of poison exons (PEs). PEs are short highly conserved exons that contain a premature truncation codon, and when spliced into the transcript, lead to premature truncation and subsequent degradation by nonsense-mediated decay. The reason for the inclusion/exclusion of these PEs is not entirely clear, but research suggests an autoregulatory role in gene expression and protein abundance. This is seen in proteins such as RNA-binding proteins and serine/arginine-rich proteins. Recent studies have focused on targeting these PEs as a method for therapeutic intervention. Targeting PEs using antisense oligonucleotides (ASOs) has shown to be effective in modulating alternative splicing events by decreasing the amount of transcripts harboring PEs, thus increasing the abundance of full-length transcripts and thereby the amount of protein in haploinsufficient genes implicated in DEE. In the age of personalized medicine, cellular and animal models of the genetic epilepsies have become essential in developing and testing novel precision therapeutics, including PE-targeting ASOs in a subset of DEEs.
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Affiliation(s)
- Miriam C Aziz
- Ken and Ruth Davee Department of Neurology, Northwestern University School of Medicine, Chicago, Illinois, USA
| | - Patricia N Schneider
- Ken and Ruth Davee Department of Neurology, Northwestern University School of Medicine, Chicago, Illinois, USA.,Instituto de Ciencias Biologicas, Universidade Federal do Para, Belem, Brazil
| | - Gemma L Carvill
- Ken and Ruth Davee Department of Neurology, Northwestern University School of Medicine, Chicago, Illinois, USA.,Department of Pharmacology and Pediatrics, Northwestern University School of Medicine, Chicago, Illinois, USA
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16
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Halford JJ, Sperling MR, Arkilo D, Asgharnejad M, Zinger C, Xu R, During M, French JA. A phase 1b/2a study of soticlestat as adjunctive therapy in participants with developmental and/or epileptic encephalopathies. Epilepsy Res 2021; 174:106646. [PMID: 33940389 DOI: 10.1016/j.eplepsyres.2021.106646] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 03/22/2021] [Accepted: 04/20/2021] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To evaluate the safety, tolerability, and pharmacokinetics of soticlestat, a first-in-class cholesterol 24-hydroxylase inhibitor, in adults with developmental and/or epileptic encephalopathies (DEE). METHODS The study comprised a 30-day, randomized, double-blind, placebo-controlled phase (Part A), followed by a 55-day open-label phase (Part B) (ClinicalTrials.gov ID: NCT03166215) . In Part A, patients with DEE and at least one bilateral motor seizure during the 4-week prospective baseline period were randomized 4:1 to receive soticlestat or placebo, in addition to their usual antiseizure medication. In Part B, all patients received open-label soticlestat. Soticlestat doses were titrated according to tolerability to a maximum of 300 mg twice daily (BID). Safety evaluations included the incidence of treatment-emergent adverse events (TEAEs). Plasma soticlestat concentrations were measured at various times for determination of multiple-dose pharmacokinetics and 24S-hydroxycholesterol (24HC). Efficacy was assessed by evaluation of changes in seizure frequency from baseline. RESULTS Eighteen patients (median age, 28.5 years) were enrolled and randomized, and 14 (78 %) completed the study. In Part A, TEAEs occurred in 71.4 % of soticlestat-treated patients and 100 % of placebo-treated patients. In Part B, the overall incidence of TEAEs was 68.8 %. In Part A, TEAEs that occurred in more than one patient in the soticlestat group were dysarthria (n = 3, 21.4 %), lethargy (n = 2, 14.3 %), upper respiratory tract infection (n = 2, 14.3 %), fatigue (n = 2, 14.3 %), and headache (n = 2, 14.3 %). Four patients discontinued treatment because of TEAEs, of whom two reported drug-related seizure clusters as serious TEAEs. There were no deaths. Pharmacokinetic analysis showed dose-dependent increases in systemic exposure and peak plasma soticlestat concentrations. At the end of Part B, the overall mean percent change from baseline in plasma 24HC was -80.97 %. Changes from baseline in median seizure frequency were +16.71 % and +22.16 % in the soticlestat and placebo groups, respectively, in Part A, and -36.38 % in all participants in Part B. CONCLUSION Soticlestat was well tolerated at doses of up to 300 mg BID and was associated with a reduction in median seizure frequency over the study duration. Further studies are warranted to assess the possible efficacy of soticlestat as adjunctive therapy in patients with DEEs such as Dravet syndrome and Lennox-Gastaut syndrome.
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Affiliation(s)
| | | | | | | | | | - Rengyi Xu
- Takeda Pharmaceuticals, Bannockburn, IL, USA
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17
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Cong Y, So V, Tijssen MAJ, Verbeek DS, Reggiori F, Mauthe M. WDR45, one gene associated with multiple neurodevelopmental disorders. Autophagy 2021; 17:3908-3923. [PMID: 33843443 PMCID: PMC8726670 DOI: 10.1080/15548627.2021.1899669] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The WDR45 gene is localized on the X-chromosome and variants in this gene are linked to six different neurodegenerative disorders, i.e., ß-propeller protein associated neurodegeneration, Rett-like syndrome, intellectual disability, and epileptic encephalopathies including developmental and epileptic encephalopathy, early-onset epileptic encephalopathy and West syndrome and potentially also specific malignancies. WDR45/WIPI4 is a WD-repeat β-propeller protein that belongs to the WIPI (WD repeat domain, phosphoinositide interacting) family. The precise cellular function of WDR45 is still largely unknown, but deletions or conventional variants in WDR45 can lead to macroautophagy/autophagy defects, malfunctioning mitochondria, endoplasmic reticulum stress and unbalanced iron homeostasis, suggesting that this protein functions in one or more pathways regulating directly or indirectly those processes. As a result, the underlying cause of the WDR45-associated disorders remains unknown. In this review, we summarize the current knowledge about the cellular and physiological functions of WDR45 and highlight how genetic variants in its encoding gene may contribute to the pathophysiology of the associated diseases. In particular, we connect clinical manifestations of the disorders with their potential cellular origin of malfunctioning and critically discuss whether it is possible that one of the most prominent shared features, i.e., brain iron accumulation, is the primary cause for those disorders. Abbreviations: ATG/Atg: autophagy related; BPAN: ß-propeller protein associated neurodegeneration; CNS: central nervous system; DEE: developmental and epileptic encephalopathy; EEG: electroencephalograph; ENO2/neuron-specific enolase, enolase 2; EOEE: early-onset epileptic encephalopathy; ER: endoplasmic reticulum; ID: intellectual disability; IDR: intrinsically disordered region; MRI: magnetic resonance imaging; NBIA: neurodegeneration with brain iron accumulation; NCOA4: nuclear receptor coactivator 4; PtdIns3P: phosphatidylinositol-3-phosphate; RLS: Rett-like syndrome; WDR45: WD repeat domain 45; WIPI: WD repeat domain, phosphoinositide interacting
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Affiliation(s)
- Yingying Cong
- Department of Biomedical Sciences of Cells & Systems, Molecular Cell Biology Section, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Vincent So
- Department of Biomedical Sciences of Cells & Systems, Molecular Cell Biology Section, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Marina A J Tijssen
- Department of Neurology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Expertise Center Movement Disorders Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Dineke S Verbeek
- Expertise Center Movement Disorders Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Fulvio Reggiori
- Department of Biomedical Sciences of Cells & Systems, Molecular Cell Biology Section, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Expertise Center Movement Disorders Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Mario Mauthe
- Department of Biomedical Sciences of Cells & Systems, Molecular Cell Biology Section, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Expertise Center Movement Disorders Groningen, University Medical Center Groningen, Groningen, The Netherlands
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18
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Banne E, Abudiab B, Abu-Swai S, Repudi SR, Steinberg DJ, Shatleh D, Alshammery S, Lisowski L, Gold W, Carlen PL, Aqeilan RI. Neurological Disorders Associated with WWOX Germline Mutations-A Comprehensive Overview. Cells 2021; 10:824. [PMID: 33916893 PMCID: PMC8067556 DOI: 10.3390/cells10040824] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 03/30/2021] [Accepted: 04/01/2021] [Indexed: 12/13/2022] Open
Abstract
The transcriptional regulator WW domain-containing oxidoreductase (WWOX) is a key player in a number of cellular and biological processes including tumor suppression. Recent evidence has emerged associating WWOX with non-cancer disorders. Patients harboring pathogenic germline bi-allelic WWOX variants have been described with the rare devastating neurological syndromes autosomal recessive spinocerebellar ataxia 12 (SCAR12) (6 patients) and WWOX-related epileptic encephalopathy (DEE28 or WOREE syndrome) (56 patients). Individuals with these syndromes present with a highly heterogenous clinical spectrum, the most common clinical symptoms being severe epileptic encephalopathy and profound global developmental delay. Knowledge of the underlying pathophysiology of these syndromes, the range of variants of the WWOX gene and its genotype-phenotype correlations is limited, hampering therapeutic efforts. Therefore, there is a critical need to identify and consolidate all the reported variants in WWOX to distinguish between disease-causing alleles and their associated severity, and benign variants, with the aim of improving diagnosis and increasing therapeutic efforts. Here, we provide a comprehensive review of the literature on WWOX, and analyze the pathogenic variants from published and unpublished reports by collecting entries from the ClinVar, DECIPHER, VarSome, and PubMed databases to generate the largest dataset of WWOX pathogenic variants. We estimate the correlation between variant type and patient phenotype, and delineate the impact of each variant, and used GnomAD to cross reference these variants found in the general population. From these searches, we generated the largest published cohort of WWOX individuals. We conclude with a discussion on potential personalized medicine approaches to tackle the devastating disorders associated with WWOX mutations.
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Affiliation(s)
- Ehud Banne
- The Genetic Institute, Kaplan Medical Center, Hebrew University-Hadassah Medical School, Rehovot 76100, Israel;
- The Rina Mor Genetic Institute, Wolfson Medical Center, Holon 58100, Israel
| | - Baraa Abudiab
- The Concern Foundation Laboratories, The Lautenberg Center for Immunology and Cancer Research, Department of Immunology and Cancer Research-IMRIC, Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel; (B.A.); (S.A.-S.); (D.J.S.); (S.R.R.); (D.S.)
| | - Sara Abu-Swai
- The Concern Foundation Laboratories, The Lautenberg Center for Immunology and Cancer Research, Department of Immunology and Cancer Research-IMRIC, Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel; (B.A.); (S.A.-S.); (D.J.S.); (S.R.R.); (D.S.)
| | - Srinivasa Rao Repudi
- The Concern Foundation Laboratories, The Lautenberg Center for Immunology and Cancer Research, Department of Immunology and Cancer Research-IMRIC, Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel; (B.A.); (S.A.-S.); (D.J.S.); (S.R.R.); (D.S.)
| | - Daniel J. Steinberg
- The Concern Foundation Laboratories, The Lautenberg Center for Immunology and Cancer Research, Department of Immunology and Cancer Research-IMRIC, Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel; (B.A.); (S.A.-S.); (D.J.S.); (S.R.R.); (D.S.)
| | - Diala Shatleh
- The Concern Foundation Laboratories, The Lautenberg Center for Immunology and Cancer Research, Department of Immunology and Cancer Research-IMRIC, Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel; (B.A.); (S.A.-S.); (D.J.S.); (S.R.R.); (D.S.)
| | - Sarah Alshammery
- Faculty of Medicine and Health, School of Medical Sciences and Discipline of Child and Adolescent Health, The University of Sydney, Westmead 2145, NSW, Australia; (S.A.); (W.G.)
| | - Leszek Lisowski
- Translational Vectorology Research Unit, Children’s Medical Research Institute, The University of Sydney, Westmead 2145, NSW, Australia;
- Laboratory of Molecular Oncology and Innovative Therapies, Military Institute of Medicine, 04-141 Warsaw, Poland
| | - Wendy Gold
- Faculty of Medicine and Health, School of Medical Sciences and Discipline of Child and Adolescent Health, The University of Sydney, Westmead 2145, NSW, Australia; (S.A.); (W.G.)
- Molecular Neurobiology Research Laboratory, Kids Research, Children’s Hospital at Westmead and The Children’s Medical Research Institute, Westmead 2145, NSW, Australia
- Kids Neuroscience Centre, Kids Research, Children’s Hospital at Westmead, Westmead 2145, NSW, Australia
| | - Peter L. Carlen
- Krembil Research Institute, University Health Network and Department of Medicine, Physiology and BME, University of Toronto, Toronto, ON M5T 1M8, Canada;
| | - Rami I. Aqeilan
- The Concern Foundation Laboratories, The Lautenberg Center for Immunology and Cancer Research, Department of Immunology and Cancer Research-IMRIC, Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel; (B.A.); (S.A.-S.); (D.J.S.); (S.R.R.); (D.S.)
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19
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Frankish A, Diekhans M, Jungreis I, Lagarde J, Loveland JE, Mudge JM, Sisu C, Wright JC, Armstrong J, Barnes I, Berry A, Bignell A, Boix C, Carbonell Sala S, Cunningham F, Di Domenico T, Donaldson S, Fiddes IT, García Girón C, Gonzalez JM, Grego T, Hardy M, Hourlier T, Howe KL, Hunt T, Izuogu OG, Johnson R, Martin FJ, Martínez L, Mohanan S, Muir P, Navarro FCP, Parker A, Pei B, Pozo F, Riera FC, Ruffier M, Schmitt BM, Stapleton E, Suner MM, Sycheva I, Uszczynska-Ratajczak B, Wolf MY, Xu J, Yang YT, Yates A, Zerbino D, Zhang Y, Choudhary JS, Gerstein M, Guigó R, Hubbard TJP, Kellis M, Paten B, Tress ML, Flicek P. GENCODE 2021. Nucleic Acids Res 2021; 49:D916-D923. [PMID: 33270111 PMCID: PMC7778937 DOI: 10.1093/nar/gkaa1087] [Citation(s) in RCA: 543] [Impact Index Per Article: 181.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/21/2020] [Accepted: 10/24/2020] [Indexed: 12/14/2022] Open
Abstract
The GENCODE project annotates human and mouse genes and transcripts supported by experimental data with high accuracy, providing a foundational resource that supports genome biology and clinical genomics. GENCODE annotation processes make use of primary data and bioinformatic tools and analysis generated both within the consortium and externally to support the creation of transcript structures and the determination of their function. Here, we present improvements to our annotation infrastructure, bioinformatics tools, and analysis, and the advances they support in the annotation of the human and mouse genomes including: the completion of first pass manual annotation for the mouse reference genome; targeted improvements to the annotation of genes associated with SARS-CoV-2 infection; collaborative projects to achieve convergence across reference annotation databases for the annotation of human and mouse protein-coding genes; and the first GENCODE manually supervised automated annotation of lncRNAs. Our annotation is accessible via Ensembl, the UCSC Genome Browser and https://www.gencodegenes.org.
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Affiliation(s)
- Adam Frankish
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Mark Diekhans
- UC Santa Cruz Genomics Institute, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - Irwin Jungreis
- MIT Computer Science and Artificial Intelligence Laboratory, 32 Vassar St, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA 02142, USA
| | - Julien Lagarde
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, Barcelona, E-08003 Catalonia, Spain
| | - Jane E Loveland
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Jonathan M Mudge
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Cristina Sisu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA.,Department of Bioscience, Brunel University London, Uxbridge UB8 3PH, UK
| | - James C Wright
- Functional Proteomics, Division of Cancer Biology, Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK
| | - Joel Armstrong
- UC Santa Cruz Genomics Institute, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - If Barnes
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Andrew Berry
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Alexandra Bignell
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Carles Boix
- MIT Computer Science and Artificial Intelligence Laboratory, 32 Vassar St, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA 02142, USA.,Computational and Systems Biology Program, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Silvia Carbonell Sala
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, Barcelona, E-08003 Catalonia, Spain
| | - Fiona Cunningham
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Tomás Di Domenico
- Bioinformatics Unit, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Sarah Donaldson
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Ian T Fiddes
- UC Santa Cruz Genomics Institute, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - Carlos García Girón
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Jose Manuel Gonzalez
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Tiago Grego
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Matthew Hardy
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Thibaut Hourlier
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Kevin L Howe
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Toby Hunt
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Osagie G Izuogu
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Rory Johnson
- Department of Medical Oncology, Inselspital, University Hospital, University of Bern, Bern, Switzerland.,Department of Biomedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Fergal J Martin
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Laura Martínez
- Bioinformatics Unit, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Shamika Mohanan
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Paul Muir
- Department of Molecular, Cellular & Developmental Biology, Yale University, New Haven, CT 06520, USA.,Systems Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Fabio C P Navarro
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Anne Parker
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Baikang Pei
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Fernando Pozo
- Bioinformatics Unit, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Ferriol Calvet Riera
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Magali Ruffier
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Bianca M Schmitt
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Eloise Stapleton
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Marie-Marthe Suner
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Irina Sycheva
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | | | - Maxim Y Wolf
- Department of Biomedical Informatics at Harvard Medical School, 10 Shattuck Street, Suite 514, Boston, MA 02115, USA
| | - Jinuri Xu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Yucheng T Yang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA.,Program in Computational Biology & Bioinformatics, Yale University, Bass 432, 266 Whitney Avenue, New Haven, CT 06520, USA
| | - Andrew Yates
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Daniel Zerbino
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Yan Zhang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA.,Department of Biomedical Informatics, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Jyoti S Choudhary
- Functional Proteomics, Division of Cancer Biology, Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK
| | - Mark Gerstein
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA.,Program in Computational Biology & Bioinformatics, Yale University, Bass 432, 266 Whitney Avenue, New Haven, CT 06520, USA.,Department of Computer Science, Yale University, Bass 432, 266 Whitney Avenue, New Haven, CT 06520, USA
| | - Roderic Guigó
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, Barcelona, E-08003 Catalonia, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, E-08003 Catalonia, Spain
| | - Tim J P Hubbard
- Department of Medical and Molecular Genetics, King's College London, Guys Hospital, Great Maze Pond, London SE1 9RT, UK
| | - Manolis Kellis
- MIT Computer Science and Artificial Intelligence Laboratory, 32 Vassar St, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA 02142, USA
| | - Benedict Paten
- UC Santa Cruz Genomics Institute, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - Michael L Tress
- Bioinformatics Unit, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Paul Flicek
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
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20
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Gowda V, Amoghimath R, Battina M, Shivappa S, Benakappa N. Case series of early SCN1A-related developmental and epileptic encephalopathies. J Pediatr Neurosci 2021; 16:212-217. [PMID: 36160609 PMCID: PMC9496615 DOI: 10.4103/jpn.jpn_99_20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 08/27/2020] [Accepted: 10/28/2020] [Indexed: 11/23/2022] Open
Abstract
Introduction: The developmental and epileptic encephalopathies (DEEs) are a heterogeneous group of rare neurodevelopmental disorders, characterized by early onset seizures that are often intractable, electroencephalographic abnormalities, developmental delay, or regression. The SCN1A pathogenic variants can present as DEE. They are characterized by early infantile seizure onset, profound intellectual disability, and a severe hyperkinetic movement disorder. Studies are lacking, hence we are reporting a case series of early SCN1A-related DEE. The objective of the study was to report clinical and molecular aspects of early SCN1A-related DEE. Materials and Methods: A retrospective chart review of children with DEEs secondary to SCN1A pathogenic variants from January 2015 to March 2020 in a tertiary care referral center from south India. Results: Out of eleven children, seven were boys. The mean age of presentation was 3.5 months. Nine children had seizures triggered by fever. All the children presented with focal and generalized seizures along with epileptic spasms. No focal neurological deficits were noted; routine testing, neuroimaging, and metabolic tests were normal in all the cases. In all the cases, hypsarrhythmia was noted on electroencephalogram (EEG). All the children had pathogenic variants in the SCN1A gene. Five children responded to steroids, one child responded to vigabatrin, and one child responded to stiripentol, but all of them had relapsed and were refractory to other antiepileptic drugs. At follow-up, all children had developmental delays and six of them had autistic features. Conclusion: Early SCN1A-related encephalopathies should be considered in the differential diagnosis of early infantile epileptic encephalopathies. Identification of this condition is important, as treatment and outcome are different from other epileptic encephalopathies.
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21
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Ní Ghrálaigh F, Gallagher L, Lopez LM. Autism spectrum disorder genomics: The progress and potential of genomic technologies. Genomics 2020; 112:5136-5142. [DOI: 10.1016/j.ygeno.2020.09.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/01/2020] [Accepted: 09/08/2020] [Indexed: 12/27/2022]
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22
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Poison exons in neurodevelopment and disease. Curr Opin Genet Dev 2020; 65:98-102. [PMID: 32615329 DOI: 10.1016/j.gde.2020.05.030] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 05/07/2020] [Accepted: 05/21/2020] [Indexed: 12/18/2022]
Abstract
Poison exons are naturally occurring, highly conserved alternative exons that contain a premature termination codon. Inclusion of a poison exon in a transcript targets the transcript for nonsense mediated decay, decreasing the amount of protein produced. Poison exons are proposed to play an important role in tissue-specific expression, development and autoregulation of gene expression. Recently, several studies that performed systematic investigations of alternative splicing in the brain have highlighted the abundance of transcripts containing poison exons, some of which are spliced in a cell type-specific manner. Pathogenic variants in or near poison exons that result in aberrant splicing have been identified in several genes including FLNA, SCN1A and SNRPB. Improved understanding of the role of poison exons in development and disease may present opportunities to solve previously undiagnosed disease and to develop therapeutic approaches in the future.
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23
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Abstract
Developmental and epileptic encephalopathies (DEEs) can be primarily attributed to genetic causes. The genetic landscape of DEEs has been largely shaped by the rise of high-throughput sequencing, which led to the discovery of new DEE-associated genes and helped identify de novo pathogenic variants. We discuss briefly the contribution of de novo variants to DEE and also focus on alternative inheritance models that contribute to DEE. First, autosomal recessive inheritance in outbred populations may have a larger contribution than previously appreciated, accounting for up to 13% of DEEs. A small subset of genes that typically harbor de novo variants have been associated with recessive inheritance, and often these individuals have more severe clinical presentations. Additionally, pathogenic variants in X-linked genes have been identified in both affected males and females, possibly due to a lack of X-chromosome inactivation skewing. Collectively, exome sequencing has resulted in a molecular diagnosis for many individuals with DEE, but this still leaves many cases unsolved. Multiple factors contribute to the missing etiology, including nonexonic variants, mosaicism, epigenetics, and oligogenic inheritance. Here, we focus on the first 2 factors. We discuss the promises and challenges of genome sequencing, which allows for a more comprehensive analysis of the genome, including interpretation of structural and noncoding variants and also yields a high number of de novo variants for interpretation. We also consider the contribution of genetic mosaicism, both what it means for a molecular diagnosis in mosaic individuals and the important implications for genetic counseling.
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Affiliation(s)
- Hannah C Happ
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Gemma L Carvill
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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