Association of bladder cancer risk with an NAD(P)H:quinone oxidoreductase polymorphism in an ethnic Kashmiri population.

NQO1 gene polymorphism at nucleotide 609 (Pro187Ser) results in a lowering of NQO1 detoxifying activity and is associated with susceptibility to various cancers. The NQO1 genotypes were identified by RFLP in 104 bladder cancer cases and 120 control subjects in an ethnic Kashmiri population. The frequency of the variant NQO1 alleles (CT/TT) was 23.3% for controls and 32.2% for cases (P < 0.05). Overall, the variant alleles were associated with a higher risk of bladder cancer in cases than in the control group (OR = 1.90; 95% CI 1.17-3.04; P < 0.01). In addition, the variant allele genotypes (CT/TT) were associated with a risk of bladder cancer that was more than threefold higher in smokers (OR = 3.47; 95% CI 1.84-6.3; P < 0.001). Results of this study strongly suggest that the variant allele of NQO1 (Pro187Ser) may affect individual susceptibility to bladder cancer, particularly among smokers, in this ethnic Kashmiri population.