Genetic predisposition to gestational glucose metabolism and gestational diabetes mellitus risk in a Chinese population

BACKGROUND: Genome-wide association studies (GWAS) have identified several genetic variants affecting gestational glucose metabolism. However, information regarding their known associations with gestational diabetes mellitus (GDM) risk remains scarce. METHODS: This study examined the associations of 12 gestational glucose metabolism-related variants with GDM risk in a Chinese population (964 GDM cases, 1021 controls). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by logistic regression analysis. RESULTS: Rs10830963 in melatonin receptor 1B (MTNR1B) was found to be associated with an increased risk of GDM, after adjusting for age, prepregnancy body mass index, parity, abnormal pregnancy history, and family history of diabetes (OR 1.20; 95% CI 1.05-1.36; P = 0.007). Compared with women with a family history of diabetes, there was a significant association of rs7936247 with GDM risk among pregnant women without a family history of diabetes (OR 1.20; 95% CI 1.04-1.38; P = 0.014; Pheterogeneity  = 0.035). Further functional annotations showed that rs10830963 and rs7936247 fell in the functional elements of human pancreatic islets. Genotype-phenotype associations indicated that the variants may contribute to GDM risk by affecting the expression of nearby or distant genes. CONCLUSIONS: The findings of this study suggest that rs10830963 and rs7936247 may be markers for susceptibility to GDM in a Chinese population. Additional studies are warranted to validate our findings and clarify the underlying mechanism.