Abstract
The $\beta$3-adrenergic receptor ($\beta$3AR) plays a major role in thermogenesis and lipolysis in brown and visceral adipose tissue, and has been implicated in the pathogenesis of obesity and metabolic disorders. The purpose of this study was to estimate the effects of $\beta$3AR gene polymorphism on the risk of hyperglycemia in 980 Korean women who attended a weight loss program in a local clinic. Each subject s height, weight, BMI, WHR, obesity index and body composition were measured. The genotype of the $\beta$3AR gene in codon 64 was analyzed by the PCR RFLP method. Serum concentrations of fasting glucose, of total and HDL cholesterol, and of TG were determined. Genotype distributions were as follows : 67% WW type, 31% WR type, and 2% RR type. Among the many measured parameters, fasting glucose levels were significantly higher in the WR/RR type compared with the WW type (p=0.0ll). When the subjects were divided into two groups by a fasting blood glucose level higher or lower than 6.105mmol/L (110mg/dl), the frequency of hyperglycemia showed a significant difference in relation to $\beta$3AR genotype as measured by $\X^2$-analysis (p=0.014); the frequency of hyperglycemia was significantly higher (at 24.8%) in WR/RR type subjects, compared to 18.2% in WW type subjects. When all of the measured parameters were included in stepwise logistic regression analyses to find the risk factors for hyperglycemia, the odds ratios for hyperglycemia were 1.573 (p=0.0ll) for the WR/RR type of the $\beta$3AR gene, 1.053 (p=0.001) for TG, 1.044 (p=0.037) for BMI, and 1.026 for age (p=0.031). These data suggest that the WR/RR genotype of the $\beta$3AR has a very strong association with increased blood glucose level and might be a significant risk factor for hyperglycemia among Korean women.