Objective: To investigate whether the ADRA2B D/I polymorphism is associated with anthropometric, metabolic, and blood pressure phenotypes in a Chinese population.
Methods: In 1306 participants enrolled in the JingNing population study, we measured anthropometry, blood pressure, plasma glucose, and serum lipids, and genotyped the ADRA2B D/I polymorphism. We defined overweight (BMI >or= 25 kg/m2) and obesity (BMI >or= 30 kg/m2) according to the WHO criteria.
Results: Genotype frequencies of the ADRA2B D/I polymorphism were significantly (P=0.02) different between 228 (17.5%) overweight and obese participants and 1078 normal weight participants, but similar between 317 (24.3%) hypertensive participants and 989 normotensive participants. After adjustment for covariates, the ADRA2B DD compared with II homozygotes had significantly (P <or= 0.01) lower BMI (21.9 versus 22.5 kg/m2), waist-to-hip ratio (0.835 versus 0.847), and triceps skinfold thickness (1.18 versus 1.27 cm) and had a significantly lower risk of overweight and obesity (odds ratio 0.52, 95% confidence interval, 0.49-0.54, P=0.0001). Further analyses showed significant (P <or= 0.01) interaction between the ADRA2B D/I polymorphism and physical activity in relation to BMI and waist-to-hip ratio. In physically less active participants [energy expenditure <or=3386 kcal/day (median)], DD compared with II homozygotes had lower BMI, waist-to-hip ratio and risk of overweight and obesity by 0.6 kg/m2, 0.012 and 60.6%, respectively.
Conclusion: The ADRA2B D allele is associated with a favourable anthropometric and metabolic profile in Chinese population, especially in physically less active participants.