Association of SCN1A Gene Polymorphism with Phenytoin Response in Patients with Epilepsy: Relevance of Stratification by the History of Febrile Seizure

AIM: The SCN1A gene encodes the NaV1.1 sodium channel in central nervous system that serves as target for phenytoin. Our study aimed to investigate association of polymorphism (SNP rs3812718) with phenytoin response. MATERIALS AND METHODS: A total 120 epileptic patients who had received at least 1 year were enrolled and genotyped using TaqMan assay. They classified into phenytoin-responsive (n = 62) unresponsive groups 58). Patients also stratified according history febrile seizure (24 subgroup; 96 no subgroup) epilepsy etiology (47 idiopathic; 73 symptomatic + cryptogenic subgroup). RESULTS: frequency AA (19% vs. 11.3%) AG genotypes (43.1% 40.3%) was found be more frequent unresponsive. GG dominated responsive group (37.9% 48.4%) but not statistically significant (p > 0.05). We identified two variables associated response: 0.012) (0.014). positive between rs3812718 genotype response when by a seizures. In without seizures, higher risk unresponsiveness than 0.048; OR 3.73, 95% CI: 1.01–13.78). CONCLUSION: There responsiveness epilepsy. subgroup, increased compared genotype.