Identification of novel and de novo variant in the SCN1A gene confirms Dravet syndrome in Moroccan child: a case report.
Hinde El Mouhi, Nada Amllal, Meriame Abbassi, Ayoub Nedbour, Meryem Jalte, Jaber Lyahyai, Siham Chafai Elalaoui, Laila Bouguenouch, Sana Chaouki
Author Information
Hinde El Mouhi: Laboratory of Biomedical and Translational Research, Faculty of Medicine and Pharmacy and Dental Medicine, Sidi Mohammed Ben Abdellah University, Fez, Morocco. hinde.elmouhi@usmba.ac.ma. ORCID
Nada Amllal: Research Team in Genomics and Molecular Epidemiology of Genetic Diseases, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco.
Meriame Abbassi: Laboratory of Biomedical and Translational Research, Faculty of Medicine and Pharmacy and Dental Medicine, Sidi Mohammed Ben Abdellah University, Fez, Morocco.
Ayoub Nedbour: Unit of Medical Genetics and Oncogenetics, University Hospital Hassan II, Fez, Morocco.
Meryem Jalte: Unit of Medical Genetics and Oncogenetics, University Hospital Hassan II, Fez, Morocco.
Jaber Lyahyai: Research Team in Genomics and Molecular Epidemiology of Genetic Diseases, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco.
Siham Chafai Elalaoui: Medical Genetics Unit, CHU Ibn Sina, Rabat, Morocco.
Laila Bouguenouch: Laboratory of Biomedical and Translational Research, Faculty of Medicine and Pharmacy and Dental Medicine, Sidi Mohammed Ben Abdellah University, Fez, Morocco.
Sana Chaouki: Laboratory of Biomedical and Translational Research, Faculty of Medicine and Pharmacy and Dental Medicine, Sidi Mohammed Ben Abdellah University, Fez, Morocco.
Dravet syndrome is a severe form of epilepsy characterised by recurrent seizures and cognitive impairment. It is mainly caused by variant in the SCN1A gene in 90% of cases, which codes for the �� subunit of the voltage-gated sodium channel. In this study, we present one suspected case of Dravet syndrome in Moroccan child that underwent exome analysis and were confirmed by Sanger sequencing. The variant was identified in the SCN1A gene, and is a new variant that has never been described in the literature. The variant was found de nova in our case, indicating that it was not inherited from the parents. The variant, SCN1A c.965-2A>G p.(?), is located at the splice site and results in an unknown modification of the protein. This variant is considered pathogenic on the basis of previous studies. These results contribute to our knowledge of the SCN1A gene mutations associated with Dravet syndrome and underline the importance of genetic analysis in the diagnosis and confirmation of this disorder. Further studies are needed to better understand the functional consequences of this variant and its implications for therapeutic strategies in Dravet syndrome.
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