TCF7L2 and type 2 diabetes mellitus: A genome-wide association study (GWAS) in 2006 identified a strong T2D susceptibility locus on chromosome 10; the strongest association marked by the microsatellite marker DG10S478 [3], and also by two common SNPs: rs7903146 and rs12255372, located in TCF7L2 intron 3 and 4, respectively.