Association of a BLVRA Common Polymorphism with Essential Hypertension and Blood Pressure in Kazaks

Abstract

Biliverdin reductase A (BLVRA) is a powerful intracellular antioxidant enzyme and an antagonist to insulin-mediated glucose uptake by the cells. Increased oxidative stress and insulin-resistance (IR) are associated with increased risk for hypertension. Therefore, we hypothesized that BLVRA might be attributable to the variation of susceptibility to essential hypertension, and investigated single nucleotide polymorphism (SNP) rs699512 (Thr3Ala), the only common non-synonymous SNP within BLVRA, in population-based samples of 999 Kazak herdsmen from the villages in Xinjiang, China. The minor allele of SNP rs699512 reduced the risk of essential hypertension (age- and gender-adjusted odds ratio 0.76; 95% confidence interval 0.61–0.94; p = 0.010). Single nucleotide polymorphism rs699512 showed association with both systolic and diastolic blood pressures: the minor allele homozygous carriers had lowest systolic and diastolic blood pressures (139.6 mmHg, 89.6mmHg), followed by heterozygous carriers (145.3 mmHg, 92.3 mmHg), and then major allele homozygous carriers (150.3 mmHg, 95.1 mmHg) (p = 0.005 and 0.009, respectively). These findings provide the first genetic evidence for the role of BLVRA on the susceptibility to human essential hypertension and blood pressure.