TCF7L2 variants have been found to have a positive association with T2DM in French (Cauchi et al. 2006), African-American (Sale et al. 2007), Finnish (Scott et al. 2006), U. K. (Groves et al. 2006), Japanese (Miyake et al. 2008), Indian (Chandak et al. 2007) and Chinese (Chang et al. 2007) populations. This evidence concerns the gene TCF7L2 and type 2 diabetes mellitus.