TCF7L2 and gestational diabetes: Of the 6 loci, Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2), Melatonin receptor 1B (MTNR1B), Transcription factor 7-like 2 (TCF7L2) are involved in insulin secretion19, 20, 21; Insulin receptor substrate 1 (IRS1) and Peroxisome proliferator-activated receptor gamma (PPARG) are involved in insulin resistance22, 23; while Tumor necrosis factor alpha (TNF-α) is involved in inflammation in DM and/or GDM pathogenesis (Supplementary Table 2)24.