Lack of association between C3435T nucleotide MDR1 genetic polymorphism and multidrug-resistant epilepsy.

The variability of P-glycoprotein expression in individuals is linked to a C3435T polymorphism of the multidrug-resistance 1 (MDR1) gene, and the CC genotype at the C3435T polymorphism was reported to be associated with multidrug resistance in epilepsy patients. Since population frequencies of polymorphic genes depend on ethnic specificity, we investigated functional significance of the C3435T polymorphism of the MDR1 gene in Korean epilepsy patients. One hundred and eight patients with drug-responsive epilepsy, 63 patients with drug-resistant epilepsy, and 219 control migraine subjects were studied, but the analysis for C3435T allele showed no significant association between the CC genotype and the multidrug-resistant epilepsy. We suggest that influence of the C3435T polymorphism in the multidrug-resistant epilepsy may not be significant in Korean populations and further investigations in various ethnic populations would be necessary to clarify the effect of C3435T polymorphism on the mutidrug resistance in epilepsy patients.