HNF1B and type 2 diabetes mellitus: Candidate-gene studies have provided strong evidence that common variants in the peroxisome proliferator-activated receptor-r (PPARG) [20], potassium inwardly-rectifying channel J11 (KCNJ11) [21]–[23], transcription factor 2 isoform b (TCF2) [24],[25], and Wolfram syndrome 1 (WFS1) [26] genes are associated with T2D.