The objective of the study is to assess the association between rs1801278 and rs2943641 of insulin receptor substrate 1 gene (IRS1) and the susceptibility to type 2 diabetes. A literature search strategy was conducted to identify all references lists of relevant studies. The fixed or random effect model was used to calculate the pooled ORs on the basis of heterogeneity. Further analyses were performed to explore the sources of heterogeneity by sensitivity analysis, meta-regression analysis, and subgroup analysis. There was significant association between rs1801278 and type 2 diabetes risk in recessive model (AA vs. GA + GG, p = 0.043) and codominant model (AA vs. GG, p = 0.007). Subgroup analysis showed that the association between rs1801278 and type 2 diabetes risk was significant in dominant model (GA + AA vs. GG, p = 0.044), codominant model (GA vs. GG, p = 0.039), codominant model (AA vs. GG, p = 0.044), overdominant model (GG + AA vs. GA, p = 0.037) in Asian and codominant model (AA vs. GG, p = 0.039) in Caucasian of rs1801278. The association between rs2943641 and type 2 diabetes risk was significant in codominant model (CT vs. CC, p = 0.023) in Caucasian. This meta-analysis suggests that rs1801278 may play a role in type 2 diabetes risk, especially in Asian. It also indicates that rs2943641 may be associated with type 2 diabetes risk in Caucasian. Further larger studies should be performed to warrant confirmation.
Keywords: IRS1; Meta-analysis; Polymorphism; Susceptibility; Type 2 diabetes.