Association between renin-angiotensin system gene polymorphism and essential hypertension: a community-based study.

Renin-angiotensin (RAS) genes, a group of promising candidate genes involved in essential hypertension (EH), play a key role in blood pressure regulation. Recently, a series of novel RAS gene polymorphisms were reported, which significantly influence the rate of the gene transcription. This study was designed to explore the association between the RAS gene polymorphisms and EH in a remote countryside population. We examined six polymorphisms in the main component genes of RAS: angiotensin-converting enzyme (ACE) (I/D), angiotensinogen (AGT) (A-6G, A-20C, G-217A and T174 M) and angiotensin type 1 receptor (AT1R) (A1166C). Six polymorphisms were genotyped by gene chip technology. Association studies were performed in 220 EH patients and 235 normotensives. Our results revealed that AGT A-6G, T174 M and ACE-I/D were significantly associated with EH (AGT A-6G: AG+GG vs AA; OR=1.36; 95% CI=1.04-1.77. T174M: CT+TT vs CC; OR=1.45; 95% CI=1.15-1.90. ACE I/D: ID+DD vs II; OR=1.171; 95% CI=1.00-1.37). Moreover the logistic regression analysis suggested that the haplotype of AGT -6A, 174C, -217G and -20A might decrease the risk of EH (OR=0.64; 95% CI=0.49-0.83), after adjusting the confounding factors of gender, age and BMI. In conclusion, the AGT A-6G, T174 M and ACE I/D polymorphisms are associated with EH and the AGT haplotype -6A, 174C, -217G and -20A decrease the risk of EH in the southern Chinese population.