GSTM1 null allele is a risk factor for gastric cancer development in Asians

Glutathione S-transferase M1 (GSTM1), which plays an important role in detoxification pathways to protect against damage caused by reactive metabolites of chemicals, has been considered as potential gastric cancer susceptibility genes. However, the published data on the association between GSTM1 present/null polymorphism and gastric cancer risk are still inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. Totally, 44 studies including 5440 cases and 11607 controls were involved in the analysis. When all studies were pooled into the meta-analysis, obviously increased gastric cancer risk was found in null genotype carriers (OR = 1.19, 95% CI: 1.08–1.33). When stratified by ethnicity, obviously evaluated risk was found in Asians (OR = 1.31, 95% CI: 1.11–1.54) but not reached to statistically significance in Caucasians (OR = 1.11, 95% CI: 0.96–1.28). In the subgroup analysis by hospital-based studies or population-based studies, statistically significantly elevated risk was found in hospital-based studies (OR = 1.34, 95% CI: 1.07–1.67) but not reached to statistically significance in population-based studies (OR = 1.11, 95% CI: 0.99–1.25). In summary, this meta-analysis result indicates that the GSTM1 null genotype is a low-penetrant risk factor for gastric cancer development in Asians.