RESUMO
Genetic differences between ethnic populations affect susceptibility to disease and efficacy of drugs. This study examined and compared the prevalence of single nucleotide polymorphisms (SNPs) in genes of the renin-angiotensin system (RAS) in a desert community of Indigenous Australians and in non-Indigenous Australians. The polymorphisms were angiotensinogen, AGT G-217A (rs5049); AGT G+174A (rs4762); Angiotensin II type 1 receptor, AGTR1 A+1166C (rs5186); angiotensin converting enzyme, ACE A-240T (rs4291), ACE T-93C (rs4292); renin, REN T+1142C (rs5706). They were measured using allelic discrimination assays. The prevalence of REN T+1142C SNP was similar in the two populations; 99% were homozygous for the T allele. All other SNPs were differently distributed between the two populations (P < 0.0001). In non-Indigenous Australians, the A allele at position 204 of ACE rs4291 was prevalent (61.8%) whereas in the Indigenous Australians the A allele was less prevalent (28%). For rs4292, the C allele had a prevalence of 37.9% in non-Indigenous Australians but in Indigenous Australians the prevalence was only 1%. No Indigenous individuals were homozygous for the C allele of AGTR1 (rs5186). Thus the prevalence of RAS SNPs in this Indigenous Australian desert community was different from non-Indigenous Australians as was the prevalence of cytokine SNPs (as shown in a previous study). These differences may affect susceptibility to chronic renal and cardiovascular disease and may alter the efficacy of drugs used to inhibit the RAS. These studies highlight the need to study the pharmacogenetics of drug absorption, distribution, metabolism and excretion in Indigenous Australians for safe prescribing guidelines.