Allelic Variability in the AGT M235Tand AT1 A1166C Single Nucleotide Polymorphisms from a Cohort of East Africans

Abstract

Non‐communicable disease (NCD), in particular cardiovascular disease, is a significant problem in developing countries. Essential hypertension (EH) is a leading risk factor for vascular diseases and while managing EH in developing countries is considered a high global priority few studies exist from third world populations. From a cohort of Kenyans living in the Kasigau region, we have investigated the allele frequency of two different single nucleotide polymorphisms (SNPs) previously reported to correlate with salt‐sensitive EH. These include the angiotensinogen (AGT) M235T (rs699) and the angiotensin II receptor Type 1 (AT1) A1166C (rs5186) alleles, both part of the renin‐angiotensin system (RAS). Overall, the genotype distribution for AGT was 86% C/C, 11% C/T, and only 3% T/T. When evaluated as normotensive, pre‐hypertensive, Stage I, and Stage II categories, the allelic frequency for f(C) = 0.76, 0.86, 0.81, and 0.76, respectively and did not demonstrate Hardy‐Weinberg equilibrium as assessed by χ2, p < 0.005. The AT1 gene frequency was 95% A/A, 5% A/C, and 0% C/C. These results are the first to identify allelic frequencies in RAS which may be linked to the prevalence of EH in East Africans and suggest that nonrandom mating or genetic drift may be responsible for the evolutionary selective pressure. This work was supported by the National Institute of General Medical Sciences of the National Institutes of Health under award number 8 P20 GM103436–12.