A case-control study of association between genetic polymorphisms of metabolizing enzymes GSTM1 and lung cancer susceptibility for the people living in high radon-exposed area

A case-control study was performed with 53 lung cancer patients and 72 frequency-matched controls to assess the role of genetic polymorphisms of metabolizing enzymes Glutathione S-transferases M1(GSTM1) in risk of developing lung cancer for the people living in high radon-exposed area. The associations between genotypes and risk of developing lung cancer were estimated by odds ratios (ORs) and their 95% confidence intervals (CIs) calculated by unconditional logistic regression. The frequencies of GSTM1 positive polymorphism and null polymorphism were 38.9% and 64.1% respectively in lung cancer patients. The frequencies of GSTM1 positive polymorphism and null polymorphism were 43.1% and 56.9% respectively in controls. The risk of developing lung cancer for GSTM1 null polymorphism was 1.35-fold(95%CI 0.652-2.81). GSTM1 null polymorphism with effective dose <50 mSv could increase the risk of developing lung cancer (OR 1.14, 95%CI 0.198-6.60). The frequency of GSTM1 positive polymorphism of lung cancer patients was lower than that of the controls. Based on those data, the frequency of GSTM1 null polymorphism of lung cancer patients was higher than that of the controls. There was an association between genetic polymorphism of GSTM1 and lung cancer. But the differences were not all statistically significant. (authors)