Genetic prediction of postpartum diabetes in women with gestational diabetes mellitus

AimsTo examine whether genetic variants that predispose individuals to type 2 diabetes (T2D) could predict the development of diabetes after gestational diabetes mellitus (GDM).Methods13 SNPs (FTO rs8050136, CDKAL1 rs7754840 and rs7756992, CDKN2A/2B rs10811661, HHEX rs1111875, IGF2BP2 rs1470579 and rs4402960, SLC30A8 rs13266634, TCF7L2 rs7903146, PPARG rs1801282, GCK rs1799884, HNF1A rs1169288, and KCNJ11 rs5219) were genotyped in 793 women with GDM after a median follow-up of 57 months.ResultsAfter adjustment for age and ethnicity, the TCF7L2 rs7903146 and the FTO rs8050136 variants significantly predicted postpartum diabetes; hazard ratio (95% confidence interval 1.29 (1.01–1.66) and 1.36 (1.06–1.74), respectively (additive model) versus 1.45 (1.01–2.08) and 1.56 (1.06–2.29) (dominant model)). Adjusting for BMI attenuated the effect of the FTO variant, suggesting that the effect was mediated through its effect on BMI. Combining all risk alleles to a weighted risk score was significantly associated with the risk of postpartum diabetes (hazard ratio 1.11, 95% confidence interval 1.05–1.18, p = 0.00016 after adjustment for age and ethnicity).ConclusionsThe TCF7L2 rs7903146 and FTO rs8050136 polymorphisms, and particularly a weighted risk score of T2D risk alleles, predict diabetes after GDM. Further studies in other populations are needed to confirm our results.