In fact, there were no other genetic studies of type 2 diabetes in the population of Hyderabad when the corresponding author of this manuscript initiated a project in the year 2009 at the Indian Statistical Institute (ISI), Hyderabad, and 15 SNPs belonging to nine genes that were known to be involved in blood-glucose homeostasis—TCF7L2 [19], insulin secretion and action-IGF2BP2 and SLC30A8 [20], insulin signaling pathway and adipocyte differentiation—IRS1, CAPN10 and PPARG [21] and pancreatic beta cell development-CDKAL1, CDKN2A/B and HHEX [22] were genotyped. This evidence concerns the gene TCF7L2 and type 2 diabetes mellitus.