In order to reveal and characterise genetic events occurring in renal tumorigenesis, samples of sporadic renal cell carcinomas (RCCs) were examined using restriction landmark genomic scanning (RLGS), an electrophoretic separation technique which detects gene amplification and deletion. We were able to find two fragments frequently amplified and 10 others commonly showing reduced signal intensity within the 16 tumour samples analysed. These altered spots were located on chromosomes 2, 3, 9-12, 16, 17 and 18 according to chromosomal assigned RLGS. A subset of reduced fragments appeared to be correlated to tumour type and were located within a new chromosomal region, suggesting genetic specificity within the process of renal carcinogenesis.