The GSTM1/ GSTT1 double-null genotype was associated with the elevated risk of bladder cancer in Caucasians (OR=1.23, 95%CI=1.08-1.40), Asians (OR=2.05, 95%CI=1.53-2.74) and Africans (OR=6.29, 95%CI=1.62-24.47). This evidence concerns the gene GSTM1 and urinary bladder cancer.