TCF7L2 and type 2 diabetes mellitus: A large meta-analysis demonstrated significant association between IVS3C > T as well as IVS4G > T TCF7L2 gene polymorphisms and T2DM where among IVS3C > T polymorphism, TC heterozygotes and TT homozygous variants increased risk of T2MD by 1.4-fold and 2.0-fold, respectively, as compared to wild-type CC homozygotes whereas in case of IVS4G > T polymorphism, TG heterozygotes and TT homozygous variants increased risk of T2MD by 1.4-fold and 1.9-fold, respectively, as compared to wild-type GG homozygotes (Tong et al. 2009).