In this work, we have conducted a case-control study in order to assess the effect of tobacco and three genetic polymorphisms in XPC, ERCC2 and ERCC5 genes (rs2228001, rs13181 and rs17655) in bladder cancer development in Tunisia. We have also tried to evaluate whether these variants affect the bladder tumor stage and grade.

Background: Susceptibility to bladder cancer is thought to depend on interplay between genetic factors and environmental chemical carcinogens. Aim: This study seeks to determine the role of the glutathione transferases M1 and T1 null genotypes (GSTM1*0 and GSTT1*0) in individual susceptibility to bladder cancer in a Tunisian population. Method: Sixty-two patients with transitional cell carcinoma of the bladder cancer and 79 controls were examined with respect to the frequency of GSTM1 and GSTT1 null genotypes. Results: The frequencies of the GSTT1 null in the total group of bladder cancer cases vs. controls did not differ statistically. The proportion of GSTM1 null genotype in patients was 63% compared to 45% in controls group (OR = 2.03; 95% CI 0.97–4.24; p = 0.04). A significantly higher incidence of GSTM1 deletion genotype was found in smokers with bladder cancer compared to the controls (65.38% vs. 45.5%). Smokers lacking the GSTM1 gene are at an approximately 2.2-fold higher risk of bladder cancer (OR = 2.23, 95% CI 1–5.15; p = 0.03). Conclusion: This study suggests that in Tunisian subjects the GSTM1 null genotype may be associated with an increased risk of bladder cancer. This association appears to depend upon smoking status.