Lack of Association of CYP2C9:c.430C>T and SCN1A:c.3184A>G Polymorphisms with Epilepsy Risk or Drug Resistance in Childhood Epilepsy Syndromes in Lagos State, Nigeria

Pharmacoresistance has been a constant challenge in managing children with childhood epilepsy syndromes, and this has been attributable in part to genetic polymorphisms in sodium ion channels and cytochrome P450 enzymes in non-Nigerian populations. Using a case-control study design, this research investigated the association of CYP2C9:c.430C>T and SCN1A:c.3184 A>G polymorphisms with drug response in a group of Nigerian infants diagnosed having epilepsy syndromes. Restriction fragment length polymorphism and tetra-primer polymerase chain reaction were used to genotype SCN1A:c.3184A>G and CYP2C9:c.430C>T polymorphisms in 22 patients (13 drug-resistant and 9 drug-responsive patients) having epilepsy syndromes and 23 age-, sex- and ethnically matched controls. This study revealed no significant difference in cases and controls carrying the CYP2C9:c.430C>T wild-type (CC) and heterozygous genotypes (CT) (P = 0.3914; OR, 1.932; 95% CI, 0.4075–7.298) or homozygous (TT) (P = 0.4024; OR, 0.4167; 95% CI, 0.0626–3.350) genotypes. In the drug-responsive vs drug-resistant group, the CYP2C9 genotypes or alleles also showed no significant difference (P > 0.05). The SCN1A:c.3184 A>G polymorphism reports showed no significant difference in the cases and controls carrying the SCN1A:c.3184 A>G wild-type (AA) and heterozygous (AG) genotypes (P = 0.467; OR, 0.6176; 95% CI, 0.1903–2.166). Both cases and controls had no occurrence of homozygous mutant (GG) genotypes. In the drug-responsive vs drug-resistant group, the SCN1A genotypes or alleles were not significantly different (P > 0.05). We concluded from this study that there is no relationship between CYP2C9:c.430C>T or SCN1A:c.3184A>G polymorphisms and epilepsy risk or pharmacoresistance in the studied groups.