CYP2C19 and CES1 gene variants affecting clopidogrel metabolism in a South Asian population from Sri Lanka.

Aims: Clopidogrel exhibits substantial variability in therapeutic response, largely contributed by genetic factors. The pharmacogenomic variants data on clopidogrel metabolism in South Asians have been sparsely studied. This study explores the impact of CYP2C19 and CES1 gene variants on clopidogrel metabolism in Sri Lankans, revealing significant pharmacogenomic insights with broader implications for South Asians.

Materials & methods: Genotype data were filtered out from an anonymized database of 690 Sri Lankans, and minor allele frequencies (MAFs) were calculated. Five variants of CYP2C19 and one variant of CES1 gene were studied.

Results: Among the five CYP2C19 variants studied, rs12769205 (A>G) and rs4244285 (G>A) had the highest MAF of 42.1% and 42.0%, respectively. The CES1 variant rs71647871 (C>T) showed a MAF of 0.2%. Sri Lankans exhibited significantly higher MAFs for key variants compared to populations such as Europeans, African Americans, and East Asians (p < 0.05).

Conclusion: Given that South Asians share genetic similarities, these findings suggest that a substantial proportion of the region's population may also be poor responders to clopidogrel, increasing the risk of adverse outcomes. This highlights the importance of genotype-guided antiplatelet therapy, which could improve clinical outcomes across South Asia amidst rising cardiovascular disease rates.