ABSTRACT
Objective To comprehensively evaluate the relationship between murine double minute 2 (MDM2) gene promoter SNP309 T＞G polymorphism and the susceptibility of gastrointestinal cancer.Methods The China National Knowledge Infrastructure (CNKI),WanFang database,SpringerLink database and PubMed were retrieved to get all case-control research literatures (2005-2012) on the relationship of MDM2 gene SNP309 T＞G and gastrointestinal cancer susceptibility.Meta-analysis with RevMan 4.2 was used to combine OR values of the relationship between SNP309 T＞G and gastrointestinal cancer susceptibility.A sensitivity analysis and tested publication bias were made with all selected literatures' data.Results A total of 17 domestic and foreign qualified papers were included in this study.Twenty case-control studies including 5 183 cases and 6 660 controls were identified for the present meta-analysis.A significant association was detected between the MDM2 SNP309 T＞G polymorphism and gastrointestinal cancer risk.The meta-aualysis showed that the combined odds ratio (OR) for GG genotype was 2.23 (95 ％ CI =1.73-2.89,P ＜ 0.01) compared with that for TG + TT genotypes.There was no statistical significance for the evaluation of publication bias.Conclusion The GG genotype of MDM2 SNP309 may increase gastrointestinal cancer risk in Asians.