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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Analysis of Variance, Carcinoma, Transitional Cell, Case-Control Studies, Confidence Intervals, Female, Gene Deletion, Genotype, Glutathione Transferase, Humans, Korea, Male, Middle Aged, Odds Ratio, Risk, Smoking, Urinary Bladder Neoplasms.
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Is gSTT1-null genotype a protective factor against bladder cancer? Context: To investigate the effects of homozygous deletions of GSTM1 and GSTT1 and smoking on bladder cancer, we conducted a case-control and ecological study. The case group consisted of 216 patients with bladder cancer and the control group of 449 healthy Koreans. Every subject was personally interviewed to obtain a detailed smoking history, and a multiplex polymerase chain reaction method was used to detect the presence or absence of the GSTM1 and GSTT1 genes. In the ecological study, age-standardized bladder cancer incidence and frequencies of GSTM1 and GSTT1-null types, estimated prevalence of cigarette smoking, and estimated per capita consumption of cigarettes per adult according to nationality and ethnicity were included. In the Korean case-control data, smoking history and the GSTT1-null genotype were significantly associated with bladder cancer, and the GSTM1-null genotype was not. In the univariate and multivariate analyses with the ecological data of various countries and ethnic groups, cigarette smoking positively, but the frequency of the GSTT1-null type negatively, correlated with the age-standardized bladder cancer incidence.
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These results suggest that the GSTT1-negative genotype might not be a risk factor but a protective factor of bladder cancer. Final Decision: yes