Gene-wide tagging study of the association between ABCC2, ABCC5 and ABCG2 genetic polymorphisms and multidrug resistance in epilepsy

Aim: To determine the association between polymorphisms of the multidrug transporter genes ABCC2, ABCC5 and ABCG2, and drug resistance in epilepsy by genotyping comprehensive sets of tagging SNPs. Materials & methods: A total of 25 tagging SNPs from ABCC2, ABCC5 and ABCG2 genes were genotyped in a total of 590 Han Chinese epilepsy patients (262 drug resistant and 328 drug responsive). Genotype and allele distributions in drug-responsive and drug-resistant patients were compared. Results: Genotype distributions of all the selected SNPs were consistent with Hardy-Weinberg equilibrium. None of the polymorphisms, either genotype or allele distributions, were significantly associated with drug resistance. For each gene, no haplotypes of over 1% frequency, and that included all SNPs of the gene, were associated with drug resistance. Conclusion: This gene-wide tagging study revealed no association between ABCC2, ABCC5 and ABCG2 genetic polymorphisms and multidrug resistance in epilepsy.