Ethnic variability in the allelic distribution of pharmacogenes between Korean and other populations.

Objective: We examined the differences in allele frequencies for pharmacogenes among the Korean (KOR), Chinese (CHB), Japanese (JPT), Caucasian (CEU), and Nigerian (YRI) populations.

Methods: Fifty-seven pharmacogenes were selected from the imputed Korean Association REsource and HapMap databases. Minor allele frequencies were analyzed using the sample size-modified single nucleotide polymorphism-specific fixation index (FST) and the χ-test with Bonferroni's correction. Geneset analysis was also carried out to identify pharmacogenes that have significantly different allele frequencies among the various populations tested.

Results: The KOR population was the most divergent group from the YRI population (FST: 0.079) but very similar to the CHB and JPT populations (FST: 0.003). VKORC1 showed a large population divergence in the KOR-YRI (0.439) comparison. CYP3A4 was also highly divergent in the KOR-YRI (FST: 0.361) comparison. The calcium signaling pathway gene set was divergent in all pairwise population comparisons.

Conclusion: In terms of the 57 pharmacogenes studied, there were no significant differences among the KOR, CHB, and JPT populations. However, the YRI and CEU populations were significantly differentiated from the three Eastern Asian groups. Future pharmacogenomics studies can utilize the polymorphisms identified in this study, as these variants may have important implications for the selection of highly informative single nucleotide polymorphisms for future clinical trials.