In the prostate cancer group, the number of subjects with GSTT1 gene copy numbers of 0, 1, 2, and > 2 was 33, 25, 16, and 11, respectively, and the number of subjects with GSTM1 gene copy numbers of 0, 1, 2, and > 2 was 46, 20, 10, and 9, respectively. This evidence concerns the gene GSTM1 and prostate cancer.