Genome wide association studies (GWAS) and other studies have reported that several genetic variants (such as MTNR1B, TCF7L2, IGF2BP2, CDKAL1, GCK) are associated with increased risk of both GDM and T2DM, suggesting that these conditions might have a shared genetic background (27, 28). Here, CDKAL1 is linked to type 2 diabetes mellitus.