The purpose of the study was to compare the anthropometric and body composition variables across the uncoupling protein-2 (UCP2) gene insertion (I)/deletion(D) polymorphism. A total of 200 apparently healthy volunteers (24.6 ± 3.1 years old) were recruited via flyers and local advertisements. Following an overnight fasting, height and weight were measured by using a standardized method, and body mass index (BMI) was calculated (kg/㎡). Body composition including fat free mass (FFM) and percent body fat (%BF) was measured by using the X-scan body composition Analyzer. A tape measure was used to measure waist circumference at the umbilical level. Polymerase chain reaction followed by electrophoresis with ethidium bromide staining was used to analyse the UCP2 I/D gene polymorphism. Chi-square analysis was used to test the Hardy-Weinberg equilibrium of the relative frequency of the UCP2 polymorphism. In this study population, the relative frequencies of Ⅱ homozygotes, ID heterozygotes, and DD homozygotes were 2.0%, 30.0%, and 68.0%, respectively. The relative frequencies of the UCP2 genotype were in the Hardy-Weinberg equilibrium. One-way ANOVA followed by Tukey post-hoc, if necessary, was used to compare the mean values of the measured variables across the UCP2 genotype. With respect to the measured anthropometric and body composition variables, there were significant differences in weight (P = 0.018), FFM (P = 0.005), BMI (P = 0.045), %BF (P = 0.022), and waist circumference (P = 0.011) across the UCP2 genotype. Tukey post-hoc analyses showed that DD homozygotes had significantly higher weight (P = 0.021), FFM (P = 0.015), BMI (P = 0.013), %BF (P = 0.006), and waist circumference (P = 0.003) than Ⅱ homozygotes. When a combined group of the Ⅱ homozygotes, similar results were found in the measured obesity indices between the genotypes. In conclusion, these current findings of the study suggest that the UCP2 gene polymorphism may be genetic marker to predict one's susceptibility to the development of obesity.

Keywords: Uncoupling protein genotype, Body composition, Obesity index, Polymerase chain reaction