CYP11B2 gene polymorphism and essential hypertension among Tibetan, Dongxiang and Han populations from northwest of China.

Essential hypertension (EH) is a complex multifactorial condition influenced by both genetic and environmental factors; aldosterone synthase (CYP11B2) is a key enzyme which involves in the terminal steps of aldosterone synthesis. The result of relationship between C-344T of CYP11B2 polymorphism and EH was controversial. This study was undertaken to investigate the association of C-344T polymorphism with EH in the populations of Tibetan, Dongxiang and Han from northwest of China. A total of 2115 participants aged 18-70 years were enrolled in this study. In total, 1776 blood samples, including 545 Tibetan (305 hypertensive and 240 normotensive), 530 Dongxiang (254 hypertensive and 276 normotensive) and 701 Han (338 hypertensive and 363 normotensive), were analyzed successfully by using Snapshot minisequencing method, 30 samples were also performed by direct sequencing (5 hypertensive and 5 normotensive in each population, respectively). The frequencies of genotype and allele of CYP11B2 (C-344T) were not significantly different between EH group and control group in every ethnic population (p > 0.05). However, in female population of Tibetan, the frequencies of CC and CT genotype and C allele in EH group were higher than in control (p < 0.05) group. The frequencies of CC genotype and C allele in both the normotensive controls and EH patients in Tibetan population were higher than in Dongxiang and Han populations. Our study suggests that there is lack of association between C-344T polymorphism of CYP11B2 gene and EH in Dongxiang and Han populations, whereas the polymorphism was correlated with EH in female population of Tibetan.