Abstract: Objective To explore the correlation between polymorphism of microsomal epoxide hydrolase 1（EPHX1） A415G and susceptibility to gastrointestinal tumors.
Methods All eligible casecontrol studies published up to May 2013 were searched out from PubMed， EMABSE， CBM， VIP, WanFang and CNKI databases. Two reviewers independently identified the literature, extracted data and assessed the quality of included studies according to inclusion and exclusion criteria. Metaanalysis was performed using STATA 11.0 software to analyze. Results A total of 18 studies comprising 5852 patients and 8710 controls were finally included. The included studies showed good homogeneity in the four genetic models of GG vs. AA， GA vs. AA，GG/GA vs. AA and GG vs. GA/AA. Overall， there was no significant association between polymorphism of EPHX1 A415G and susceptibility to gastrointestinal tumors［GG vs. AA： OR=1.063， 95％CI： 0.888-1.273； GA vs. AA： OR=0.935， 95％CI： 0.867-1.009；GG/GA vs. AA： OR=0.948， 95％ CI： 0.882-1.020； GG vs. GA/AA： OR=1.091， 95％ CI： 0.913-1.304］. Conclusion This metaanalysis suggest that there is no correlation between polymorphism of EPHX1 A415G and susceptibility to gastrointestinal tumors.