Association of tumor necrosis factor-α (TNF-α) promoter polymorphisms with overweight/obesity in a Korean population

Abstract

Objective Obesity is characterized by the activation of an inflammatory process leading to an increase in proinflammatory cytokines and adipokines. This study was designed to investigate the genetic association between tumor necrosis factor-a (TNF-a) polymorphisms and the risk of obesity in the Korean population. Methods Three single nucleotide polymorphisms [G-238A (rs361525), C-857T (rs1799724), and C-863A (rs1800630)] in the promoter region of TNF-a gene were analyzed in 123 control [body mass index (BMI) between 18 and 23] and 208 overweight/obese (BMI C 23) subjects. Results The mean values of BMI in the control and overweight/ obese groups were 21.1 ± 1.4 and 25.4 ± 1.8, respectively. Of the three SNPs, G-238A presented a significant association with overweight/obesity in the codominant model; the frequency of the G/G genotype in the overweight/obese group was 9.3%higher than that in the control group (P = 0.0046). When control and overweight/ obesity subjects were combined together and analyzed, the level of high-density lipoprotein (HDL) was significantly higher in the C-857T C/C type SNP (P\0.05). Conclusions The results of this study suggest that the G allele of G-238A in TNF-a gene may be a risk factor for overweight/obesity in the Korean population and that the C allele of C-857T may be an protective factor in relation to the HDL level in the general Korean population. Keywords Body mass index Tumor necrosis factor Obesity/overweight Polymorphism