To establish whether or not the mutations in the BRCA1 and BRCA2 genes contribute to bladder or kidney cancer in Poland, and to measure the impact of this variant on cancer risk, we genotyped 1028 unselected patients with bladder cancer, 688 unselected cases with renal cancer, 4000 healthy controls for testing the BRCA1 gene and 2791 healthy controls for testing BRCA2 gene. The gene discussed is BRCA1; the disease is cancer.