Multidrug resistance 1 (MDR1) gene polymorphisms in childhood drug-resistant epilepsy.

Despite considerable progress in the pharmacotherapy of epilepsy, more than 30% of patients are reported to be resistant to antiepileptic drugs. Multidrug resistance 1 (MDR1) gene could play a role in drug resistance in epilepsy. In this study, the authors investigated the association between the MDR1 gene polymorphisms, C3435T and G2677AT, and drug resistance epilepsy by using polymerase chain reaction/restriction fragment length polymorphism and pyrosequencing methods in a group of 39 patients with drug-resistant epilepsy and 92 controls. No associations were found between the polymorphisms of the MDR1 gene and drug-resistant epilepsy. Haplotype analysis showed no significant association. Compound genotype analysis showed that CC3435/GG2677 was significantly higher in the control group compared to the patient group. In conclusion, MDR1 polymorphisms investigated in this study are not associated with antiepileptic drug resistance, but the CC3435/GG2677 compound genotype might have an effect on antiepileptic drug response.