Background: The beta-3 adrenergic receptor (β3-AR) Trp64Arg and uncoupling protein 1 (UCP1) -3826 A>G polymorphisms have been reported to be associated with obesity and/or lipid metabolism in some populations. This study examined the possible association of the β3-AR and UCP1 polymorphisms with overweight/obesity or lipid variation in a Southwest Chinese population.
Methods: A total of 418 Han Chinese (249 overweight/obese and 169 healthy control subjects) in the Chengdu area were studied using PCR-RFLP analysis. Total serum cholesterol (TC) and triglycerides (TGs) were measured using an enzymatic method. High density lipoprotein cholesterol (HDL-C) was determined after sodium phosphotungstate/magnesium chloride precipitation of low-density lipoproteins by polyvinyl sulfate. Serum apolipoproteins were quantified by radial immunodiffusion.
Results: The genotype and allele frequencies of the β3-AR Trp64Arg and UCP1 -3826 A>G polymorphisms in overweight/obese subjects exhibited no significant differences compared to the controls. However, subjects carrying the β3-AR TrpTrp genotype and UCP1 AG genotype had higher TG levels than those carrying the Arg allele and AA genotype, respectively (P<0.05), while controls carrying the β3-AR Arg allele had significantly higher TC and apo AII concentrations than those carrying the TrpTrp genotype (P<0.05). Additionally, subjects carrying the UCP1 AG genotype exhibited elevated apo C-II and apo C-III levels compared to those carrying the AA genotype (P<0.05). We were unable to find an association of the UCP1 and β3-AR polymorphisms with low HDL-cholesterolemia in the overweight/obese subjects.
Conclusions: The present study provides evidence that the β3-AR Trp64Arg and UCP1 -3826 A>G polymorphisms are associated with TG levels in overweight/obese Chinese subjects and that the two polymorphisms are also associated with certain lipid and apolipoprotein variations, depending on BMI. However, these polymorphisms are not associated with overweight/obesity or low HDL-cholesterolemia in a Chinese population from the Chengdu area.