Skip to main content
Top
Published in: Journal of Medical Case Reports 1/2019

Open Access 01-12-2019 | Epilepsy | Case report

Clinical exome sequencing identifies two novel mutations of the SCN1A and SCN2A genes in Moroccan patients with epilepsy: a case series

Authors: Maryem Sahli, Abdelali Zrhidri, Siham Chafai Elaloui, Wiam Smaili, Jaber Lyahyai, Fatima Zohra Oudghiri, Abdelaziz Sefiani

Published in: Journal of Medical Case Reports | Issue 1/2019

Login to get access

Abstract

Background

Epilepsy is the most common neurological disorder that causes spontaneous, unprovoked, and recurrent seizures. Epilepsy is clinically and genetically heterogeneous with various modes of inheritance. The complexity of epilepsy presents a challenge and identification of the causal genetic mutation allows diagnosis, genetic counseling, predicting prognosis, and, in some cases, treatment decisions. Clinical exome sequencing is actually becoming a powerful approach for molecular diagnosis of heterogeneous neurological disorders in clinical practice.

Case presentation

We report our observations of three unrelated Moroccan patients referred to our genetics department for molecular diagnosis of epilepsy: a 4-year-old Moroccan boy, a 3-year-old Moroccan girl, and a 7-year-old Moroccan boy. Due to the heterogeneity and complexity of epilepsy, we performed clinical exome sequencing followed by targeted analysis of 936 epilepsy genes. A total of three mutations were identified in known epilepsy genes (SCN1A, SCN2A). By clinical exome sequencing, we identified two novel mutations: c.4973C>A (p.Thr1658Lys) in SCN1A gene and c.1283A>G (p.Tyr428Cys) in the SCN2A gene, whereas the third mutation c.3295G>T (p.Glu1099*) was already described in patients with Dravet syndrome.

Conclusion

This study demonstrates that clinical exome sequencing is an effective diagnosis tool to investigate this group of diseases with huge diversity and defends its use in clinical routine.
Literature
1.
go back to reference Fiest KM, Sauro KM, Wiebe S, et al. Prevalence and incidence of epilepsy: A systematic review and meta-analysis of international studies. Neurology. 2017;88(3):296–303.CrossRef Fiest KM, Sauro KM, Wiebe S, et al. Prevalence and incidence of epilepsy: A systematic review and meta-analysis of international studies. Neurology. 2017;88(3):296–303.CrossRef
2.
go back to reference Santhosh NS, Sinha S, Satishchandra P. Epilepsy: Indian perspective. Ann Indian Acad Neurol. 2014;17(Suppl 1):S3–S11.PubMedPubMedCentral Santhosh NS, Sinha S, Satishchandra P. Epilepsy: Indian perspective. Ann Indian Acad Neurol. 2014;17(Suppl 1):S3–S11.PubMedPubMedCentral
3.
go back to reference Fisher RS, van Emde Boas W, Blume W, et al. Epileptic seizures and epilepsy: definitions proposed by the International League Against Epilepsy (ILAE) and the International Bureau for Epilepsy (IBE). Epilepsia. 2005;46(4):470–2.CrossRef Fisher RS, van Emde Boas W, Blume W, et al. Epileptic seizures and epilepsy: definitions proposed by the International League Against Epilepsy (ILAE) and the International Bureau for Epilepsy (IBE). Epilepsia. 2005;46(4):470–2.CrossRef
5.
go back to reference Myers CT, Mefford HC. Advancing epilepsy genetics in the genomic era. Genome Med. 2015;7:91.CrossRef Myers CT, Mefford HC. Advancing epilepsy genetics in the genomic era. Genome Med. 2015;7:91.CrossRef
6.
go back to reference Liu S, Yu W, Lu Y. The causes of new-onset epilepsy and seizures in the elderly. Neuropsychiatr Dis Treat. 2016;12:1425–34.CrossRef Liu S, Yu W, Lu Y. The causes of new-onset epilepsy and seizures in the elderly. Neuropsychiatr Dis Treat. 2016;12:1425–34.CrossRef
7.
go back to reference Fogel BL, Satya-Murti S, Cohen BH. Clinical exome sequencing in neurologic disease. Neurol Clin Pract. 2016;6(2):164–76.CrossRef Fogel BL, Satya-Murti S, Cohen BH. Clinical exome sequencing in neurologic disease. Neurol Clin Pract. 2016;6(2):164–76.CrossRef
8.
go back to reference Tumiene B, Maver A, Writzl K, et al. Diagnostic exome sequencing of syndromic epilepsy patients in clinical practice. Clin Genet. 2018;93(5):1057–62.CrossRef Tumiene B, Maver A, Writzl K, et al. Diagnostic exome sequencing of syndromic epilepsy patients in clinical practice. Clin Genet. 2018;93(5):1057–62.CrossRef
9.
go back to reference Epi4K Consortium; Epilepsy Phenome/Genome Project, Allen AS, et al. De novo mutations in epileptic encephalopathies. Nature. 2013;501(7466):217–21.CrossRef Epi4K Consortium; Epilepsy Phenome/Genome Project, Allen AS, et al. De novo mutations in epileptic encephalopathies. Nature. 2013;501(7466):217–21.CrossRef
10.
go back to reference Kodera H, Kato M, Nord AS, et al. Targeted capture and sequencing for detection of mutations causing early onset epileptic encephalopathy. Epilepsia. 2013;54(7):1262–9.CrossRef Kodera H, Kato M, Nord AS, et al. Targeted capture and sequencing for detection of mutations causing early onset epileptic encephalopathy. Epilepsia. 2013;54(7):1262–9.CrossRef
11.
go back to reference Allen NM, Conroy J, Shahwan A, et al. Unexplained early onset epileptic encephalopathy: Exome screening and phenotype expansion. Epilepsia. 2016;57(1):e12–7.CrossRef Allen NM, Conroy J, Shahwan A, et al. Unexplained early onset epileptic encephalopathy: Exome screening and phenotype expansion. Epilepsia. 2016;57(1):e12–7.CrossRef
12.
go back to reference Xue Y, Ankala A, Wilcox WR, Hegde MR. Solving the molecular diagnostic testing conundrum for Mendelian disorders in the era of next-generation sequencing: single-gene, gene panel, or exome/genome sequencing. Genet Med. 2015;17(6):444–51.CrossRef Xue Y, Ankala A, Wilcox WR, Hegde MR. Solving the molecular diagnostic testing conundrum for Mendelian disorders in the era of next-generation sequencing: single-gene, gene panel, or exome/genome sequencing. Genet Med. 2015;17(6):444–51.CrossRef
13.
go back to reference Usluer S, Salar S, Arslan M, et al. SCN1A gene sequencing in 46 Turkish epilepsy patients disclosed 12 novel mutations. Seizure. 2016;39:34–43.CrossRef Usluer S, Salar S, Arslan M, et al. SCN1A gene sequencing in 46 Turkish epilepsy patients disclosed 12 novel mutations. Seizure. 2016;39:34–43.CrossRef
14.
go back to reference Mancardi MM, Striano P, Gennaro E, et al. Familial occurrence of febrile seizures and epilepsy in severe myoclonic epilepsy of infancy (SMEI) patients with SCN1A mutations. Epilepsia. 2006;47(10):1629–35.CrossRef Mancardi MM, Striano P, Gennaro E, et al. Familial occurrence of febrile seizures and epilepsy in severe myoclonic epilepsy of infancy (SMEI) patients with SCN1A mutations. Epilepsia. 2006;47(10):1629–35.CrossRef
Metadata
Title
Clinical exome sequencing identifies two novel mutations of the SCN1A and SCN2A genes in Moroccan patients with epilepsy: a case series
Authors
Maryem Sahli
Abdelali Zrhidri
Siham Chafai Elaloui
Wiam Smaili
Jaber Lyahyai
Fatima Zohra Oudghiri
Abdelaziz Sefiani
Publication date
01-12-2019
Publisher
BioMed Central
Published in
Journal of Medical Case Reports / Issue 1/2019
Electronic ISSN: 1752-1947
DOI
https://doi.org/10.1186/s13256-019-2203-8

Other articles of this Issue 1/2019

Journal of Medical Case Reports 1/2019 Go to the issue