A large genetic analysis of thrifty genes in 65 T2DM index SNPs failed to identify a global signal for positive selection but detected several positively selected loci in one or more specific populations; for example, five SNPs in PROX1, GRB14, UEB2E2, IGF2BP2 and ARAP1 in African populations; three SNPs in PROX1, HMGA2 and PRC1 in European populations; and nine SNPs in NOTCH2, THADA, GRB14, WFS1, TP53INP1, TCF7L2 and PRC1 in East Asian populations [224]. Here, TCF7L2 is linked to type 2 diabetes mellitus.