Abstract
Background: Polymorphisms with decreased enzyme activity of their gene products have been reported in region CYP2C with population variations in haplotype structure.
Aim: To estimate the allelic and genotypic frequencies of variants CYP2C9*2 and CYP2C9*3 and of CYP2C9/CYP2C19 haplotypes in Venezuelan populations.
Subjects and methods: Six hundred and thirty-four individuals from nine admixed populations (AP) and the Warao indigenous group were studied. Allelic frequencies, linkage disequilibrium and genetic distances for haplotypes were calculated and compared within Venezuela and with data available in the literature.
Results: Heterogeneity in the distribution of CYP2C9 alleles and CYP2C9/CYP2C19 haplotypes among the AP and the Warao was observed. The joint frequency of haplotypes, with at least one non-functional variant, shows values in AP between 21–41%, while in Warao it reaches 5%. The haplotype that includes the Asian and rare Latin America CYP2C19*3 allele was detected in most AP and in Warao. Pairwise Fst values showed that the Warao was an outlier compared with the AP, while these are closer to European-derived populations. No significant correlation was found between haplotype frequencies and admixture.
Conclusions: These results support the need to understand the distribution of genomic biomarkers related to the metabolism of drugs, for planning national public health strategies.
Acknowledgements
We are grateful to the individuals who volunteered to participate in this study. We thank Irene Paradisi, Mary Helen Izaguirre, Diana Sierra, Marina Florez and Luis José Díaz for their technical assistance. This work was supported by Grant LOCTI-IVIC899 and the Venezuelan Institute for Scientific Research.
Disclosure statement
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.