Background: Genetics research of humans has established that a genetic basis contributes to the susceptibility to epilepsy for a majority of the cases. Although many epilepsies are secondary to injury or another illness, approximately 40% are idiopathic, meaning that the original cause is unknown. It is presumed that most idiopathic epilepsies result from genetic abnormalities, with the majority likely caused by mutations in multiple currently unidentified genes. However, research has revealed a growing number of single-gene mutations that cause epilepsy. Objective: To detect some of the genetic mutations which may cause idiopathic epilepsy. Methods: The current study is a cross-sectional study that had been performed at Sheikh Mohamed Khair center, Banat, Omdurman, and National Centre for Neurological Sciences (NCNS) Khartoum state, during the period 2016 to 2019. Ninety-nine participants were enrolled in this study. Demographic data were collected in a predesigned questionnaire blood samples were analyzed for biochemical and molecular tests. Results: Ninety-nine patients diagnosed with idiopathic epilepsy were recruited in this study. The most affected age group was 18 - 40 years accounted for 55% of patients. Females were the majority with 53%. Fifty percent of the patients had the first seizure at age less than 5 years. Ninety percent of the patients have no Family history with epilepsy. All sequenced samples showed genetic mutations, deletion mutation was detected in 71% of the samples. Bioinformatics tools detected a frameshift mutation in the chain of the amino acids. Conclusion: The current study detected deletion mutations in SCN1A gene (frameshift) can cause epilepsy by changing some amino acids with residues that can affect neuronal stability indirectly.
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