The genes fall into three main groups; known MODY (maturity-onset diabetes of the young) genes (GCK, HNF1A and PDX1)14, known genes reported in previous exome-wide analyses of glucose levels or T2D (G6PC2 and PAM)5,15, and novel genes not previously implicated by genetics in diabetes (GIGYF1, TNRC6B and PFAS). This evidence concerns the gene HNF1A and type 2 diabetes mellitus.