Objective: To investigate the association of -866A/G polymorphism of uncoupling protein 2 (UCP2) gene, and 54G/C polymorphism of sterol regulatory element binding protein 1c (SREBP1c) gene with abdominal obesity in the population of type 2 diabetes mellitus families.
Methods: Eligible type 2 diabetes mellitus cases from newly diagnosed and previous hospitalized patients were choson, then their family members (siblings and parents) tracked. A set of questionnaires was administered to obtain information on demographic characteristics. Physical measurements were recorded. DNA was extracted from blood samples and genotyped using polymerase chain reaction with restriction fragment length polymorphism (PCR-RFLP). Generalized estimating equation (GEE) was used to adjust for within-family correlation in analysis of relationships of factors.
Results: In the study population, the frequency of A allele of UCP2-866A/G polymorphism was 0.459, and of G allele 0.541; the frequency of G allele of SREBP1c 54G/C polymorphism was 0.822, and of C allele 0.178. Totally 762 participants were analyzed using GEE regression. It was shown that the odds ratio (OR) of the population with only 54G/C polymorphism of SREBP1c gene being the mutant type (GC/CC) was statistically significant while -866A/G polymorphism of UCP2 gene not being the mutant type (AG/GG) was not. The OR of the population with the opposite genotype status was 1.8 (P=0.042), and that with mutant types of both polymorphisms 3.2(P=0.001).
Conclusion: In the population of type 2 diabetes mellitus families, only 54G/C polymorphism of SREBP1c gene being the mutant type (GC/CC) might be a moderate risk factor of abdominal obesity. When both the two polymorphisms studied are the mutant type, the risk of abdominal obesity may increase significantly.