Carriers of variant Ser allele in codon 187 of NQO1 exhibited significant increased risk for bladder cancer, when compared to non-carriers (homozygous model: OR = 1.43, 95% CI = 1.08–1.90; recessive model: OR = 1.33, 95% CI = 1.03–1.72; dominant model: OR = 1.19, 95% CI = 1.04–1.37, and allele comparing: OR = 1.18, 95% CI = 1.06–1.33). The gene discussed is NQO1; the disease is urinary bladder cancer.