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Pharmacogenetic testing, where prescriptions are tailored to the individual patient based on his/her genetic makeup, increases the ability to predict individual drug response. However, little is known about the prevalence of clinically actionable pharmacogenes in diverse populations. This study seeks to assess the prevalence of select drug-gene alleles that are implicated in the metabolism of commonly prescribed drugs, so-called Very Important Pharmacogenes (VIPs). The results of this study will fill in the gaps of knowledge of VIPs in underrepresented populations and characterize their potential risk for drug adverse events or due to their underlying genetic polymorphisms, especially in patients of Asian, Hawaiian or Marshallese, or Samoan descent.

The Ensemble genome browser was used to compare the frequencies of three major single nucleotide polymorphisms (SNPs) in the cytochrome P450 subfamily 2 class 19 (CYP2C19) in European (EUR) with our studied populations. Specially, SNPs of interest included rs4244285 G>A, rs4986893 G>A, and rs12248560 C>T, for CYP2C19*2, *3, and *17, respectively. In this cross-sectional study, chi-square or Fisher’s exact test was used, when appropriate, with P < 0.05 for significance.

Biobank DNA samples of 1064 participants were used to calculate genotype and allele frequencies for our population groups. The sample was distributed across six self-reported ethnicities; Filipino (21.61%), Japanese (19.73%), Korean (9.77%), Hawaiian (14.84%), Marshallese (15.13%), and Samoan (18.89%). In each ethnicity from our population, the distributions of allele and genotype frequencies of the CYP2C19 *2 (rs4244285 G>A), *3 (rs4986893 G>A), and *17 (rs12248560 C>T) variants were significantly different from EUR.

The overall loss-of-function allele (A) frequencies of *2 (rs4244285 G>A) and *3 (rs4986893 G>A) were significantly higher in our population groups (25%-36% and 2.5%-10%, respectively) than EUR (15%, and 0%, respectively). In contrast, the overall increased function allele (T) frequencies of *17 (rs12248560 C>T) were significantly higher in EUR (22.5%) than in our population (1%-6%). In conclusion, our results are consistent with published reports of Asian populations are enriched with the reduced or loss of function alleles of CYP2C19 compared with EUR.

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Pharmacogenomics, Single Nucleotide Polymorphism (SNP), Very Important Pharmacoges (VIPs), Cytochrome P450 subfamily 2 class 19 (CYP2C19)


Other Pharmacy and Pharmaceutical Sciences

Faculty Advisor/Mentor

Youssef Roman

Is Part Of

VCU Graduate Research Posters

Frequency of Genetic Polymorphisms of CYP2C19 in Native Hawaiian, and Asian and Pacific Islander Subgroups: Implications for Personalized Medicine