Glutathione S-Transferase P1 313 (A > G) Ile105Val Polymorphism Contributes to Cancer Susceptibility in Indian Population: A Meta-analysis of 39 Case-Control Studies.

involved in the metabolism of carcinogens and toxins, reduces damage of DNA and act as a suppressor of carcinogenesis. Many studies have reported that 313 A > G polymorphism is associated with different cancer in Indian population, but the results remain conflicting rather than conclusive. Therefore, we have performed meta-analysis to clarify the more precise association of 313 A > G polymorphism with cancer risk in Indian population. We retrieved all relevant published literature from PubMed (Medline) and Google scholar web database and included those study only based on the established inclusion criteria. Pooled ORs and 95% CIs were used to appraise the strength of association. Publication bias and sensitivity analysis was also evaluated. A total of 6581 confirmed cancer cases and 8218 controls were included from eligible thirty nine case-controls studies. Pooled analysis suggested that the variant genotypes significantly increased the risk of cancer in allele (G vs. A: OR 1.266, 95% CI 1.129-1.418,  = 0.001), heterozygous (AG vs. AA: OR 1.191, 95% CI 1.047-1.355,  = 0.008), homozygous (GG vs. AA: OR 1.811, 95% CI 1.428-2.297,  = 0.001), dominant (GG + AG vs. AA: OR 1.276, 95% CI 1.110-1.466,  = 0.001) and recessive (GG vs. AG + AA: OR 1.638, 95% CI 1.340-2.002,  = 0.001) genetic models. The stability of these observations was confirmed by a sensitivity analysis. Begger's funnel plot and Egger's test did not reveal any publication bias. This meta-analysis suggests that the 313 A > G polymorphism may contribute to genetic susceptibility to cancer in Indian population. However, larger studies and randomized clinical trial will be required to elucidate the biological and molecular mechanism of gene in cancer.