Association of ABCB1 Genetic Variants with Epilepsy Susceptibility in Jordanian Cohort

Background: Epilepsy is a chronic disorder with a higher prevalence in low- and middle-income countries. ATP-binding cassette superfamily B1 (ABCB1) not only has a potential influence on the resistance to antiepileptic drugs but also plays a possible role in the occurrence of epilepsy. Purpose: To evaluate the association of ABCB1 polymorphisms, c.1236C>T (rs1128503), c.2677G>T (rs2032582), and c.3435C>T (rs1045642), with epilepsy susceptibility in a Jordanian cohort. Subjects and methods: Eighty-six cases of patients with epilepsy were analyzed using polymerase chain reaction (PCR) for ABCB1 c.1236C>T, c.2677G>T, and c.3435C>T gene variants. The proportions of genotypes and alleles in the epilepsy group were compared with one hundred healthy controls who were previously also analyzed by PCR. Results: The C alleles of the ABCB1 polymorphisms c.1236C>T and c.3435C>T were more prevalent in the epilepsy group than in controls. The patients with epilepsy were less likely to have the TT genotype compared with controls (concerning ABCB1 c.1236C>T) (ORTT vs. CC = 0.42; 95% CI = 0.19–0.91; p = 0.019). The CC genotype of ABCB1 c.3435C>T was more frequent in epileptics than healthy people (ORCC vs. TT = 4.3; 95% CI = 1.8–9.95; p = 0.0007). No significant difference in ABCB1 c.2677G>T allelic and genotypic frequencies was observed between epileptic cases and healthy volunteers. Conclusion: Our findings suggest that ABCB1 c.1236C>T and c.3435C>T variants were associated with epilepsy susceptibility in this Jordanian cohort, whereas no significant association was observed for c.2677G>T. These findings should be interpreted cautiously because of the modest sample size and require validation in larger, independent studies.