Objective To examine the frequency of C825T G protein β3 subunit gene polymorphism and its association with obesity of ethnic Kyrgyz.

Methods The study enrolled 210 people, 89 patients (35 females, 54 males) with obesity (BMI ≥ 30 kg/m2) and 121 practically healthy patients (38 females, 83 males) with normal body weight and no signs of type 2 diabetes (group of control), who were not observed before by a cardiologist. The blood pressure, anthropometry, glucose and lipid profile were examined among all subjects. Genomic DNA was extracted from peripheral blood cells. G protein β3 subunit C825T polymorphism was determined by polymerase chain reaction (PCR).

Results TT and CT genotypes carriers were grouped together in one group because the TT genotype was rare. CT + TT genotype frequency in the group with obesity made 0.72 and was significantly higher than that in the control group - 0.52 (χ²-8.44; P = 0.004; odds ratio - 2.55; 95%CI 1.31-4.23). The statistical analysis revealed that hypertension (45% vs. 31.3%, P = 0.049) and obesity (51.2% vs. 30%, P <0.01) occurred significantly more often in CT + TT genotype carriers than in the CC homozygotes. The results of the multivariate logistic regression analysis showed that the presence of 825T allele (exp β - 2.89; 95% CI 1.25-6.7; P=0.013), along with the occasional consumption of vegetables (exp β - 3.47; 95% CI 1.52-7.94; P=0.003) was the significant risk factor for obesity, regardless of gender, age and level of physical activity. In the construction of the similar regression model for hypertension, the statistically significant role of 825T allele was lost after adjustment for obesity as an independent variable.

Conclusion G protein β3 subunit gene C825T allele in the Kyrgyz ethnic group has an association with obesity.