While environmental factors such as increasingly sedentary lifestyles and obesogenic diets have a substantial impact, genetic susceptibility also plays a significant role in T2D risk (57). Correspondingly, genome-wide association studies (GWAS) have identified ∼90 loci harboring single nucleotide polymorphisms (SNPs) that confer increased disease risk (13, 21, 23, 40, 57, 65, 86). Such studies have thus led to the discovery of novel genes involved in T2D, such as T cell factor 7-like 2 (TCF7L2) (21) and SLC30A8 (58, 65). Of note, the majority of the GWAS-identified loci affect insulin secretion rather than action, further emphasising the likely role in disease etiology of impaired insulin production.