For T2D risk and the rs2237895 polymorphism of KCNQ1, our meta-analysis gave an overall OR of 1.24 (95% CI: 1.20–1.29; P<10−5; Figure 2) with statistically significant between-study heterogeneity (P<10−5). Here, KCNQ1 is linked to type 2 diabetes mellitus.