The rs266729 single-nucleotide polymorphism in the adiponectin gene shows association with gestational diabetes

Gestational diabetes mellitus (GDM) is a condition of impaired glucose tolerance during pregnancy in women without previous diagnosis of diabetes. It is associated with serious complications for both mother and child in the pre- and postnatal period. Moreover, women with GDM are at an increased risk of developing type 2 diabetes. Adiponectin is an important factor involved in the regulation of both carbohydrate and lipid metabolism. Polymorphisms in its gene (ADIPOQ) are known to affect the individual's predisposition to metabolic syndrome and type 2 diabetes. The aim of the current study was to investigate the possible association between three common single-nucleotide polymorphisms in ADIPOQ and gestational diabetes.

A total of 394 individuals were recruited to the study-130 pregnant women with GDM, 130 pregnant women without glucose intolerance and 134 female population controls. All subjects were genotyped for rs266729, rs2241766 and rs1501299 in the ADIPOQ gene.

A significant association with the disease was observed for rs266729 (p = 0.0037). The rare G allele was found to be over-represented among controls (pregnant, population and pooled). While no association was found for rs2241766 and rs1501299, a GTG haplotype formed by the three polymorphisms was found to be more common among controls (0.004).

The adiponectin promoter polymorphism rs266729 is associated with gestational diabetes. The minor G allele appears to confer protection against pregnancy-related diabetes mellitus. This effect is probably due to the influence of the variant on the adiponectin transcription regulation during gestation.