Cardiovascular and metabolic phenotypes in relation to the ADRA2B insertion/deletion polymorphism in a Chinese population

OBJECTIVE: The functional ADRA2B I/D polymorphism is associated with various cardiovascular and metabolic phenotypes in Caucasians. The purpose of our study was to investigate whether the ADRA2B I/D polymorphism is associated with such phenotypes in a Chinese population. METHODS: We enrolled 247 women and 234 men in a family-based Chinese study. Our statistical methods included generalized estimating equations and quantitative transmission disequilibrium test. RESULTS: The I allele (62.3 versus 50.8%, P = 0.015) and the II genotype (40.9 versus 23.4%, P = 0.017) were more prevalent among hypertensive than normotensive men. While adjusting for covariates and family clusters, male II homozygotes compared with D-allele carriers had higher systolic pressure (130.0 versus 125.0 mmHg, P = 0.016) and a 2.61 times greater (P = 0.008) risk of hypertension. On the other hand, II homozygous men had lower body weight (65.4 versus 69.6 kg, P = 0.008), body mass index (23.4 versus 24.5 kg/m2, P = 0.037), waist-to-hip ratio (0.838 versus 0.857, P = 0.024), serum insulin concentration (9.5 versus 13.2 mU/l, P = 0.026) and insulin resistance (homeostasis model assessment index 2.4 versus 3.2, P = 0.051). None of these associations reached statistical significance in women. In 65 informative male offspring, transmission of the I allele was associated with higher systolic pressure (+ 6.0 mmHg, P = 0.10), diastolic pressure (+ 5.5 mmHg, P = 0.021), and faster pulse rate (+ 5.8 beats/min, P = 0.019). CONCLUSION: In Chinese men, the I allele of the ADRA2B gene is associated with higher blood pressure, but also with a more favourable metabolic phenotype.status: publishe