One of the most interesting but still unsolved issues in prostate cancer is the role of androgens, the androgen receptor (AR) and the p53 tumor suppressor gene in the development and/or progression of prostatic neoplasia. DNA obtained from prostate tissues of 7 normal donors, 5 BPH and 10 adenocarcinomas at different stages was amplified by the polymerase-chain-reaction (PCR). The products were analysed by single strand conformation polymorphism (SSCP), and by direct sequencing of those that displayed altered electrophoretic behavior. The molecular analysis of exons 1 to 8 of the AR gene revealed point mutations in codons 340 (exon 1) and 798 (exon 6) in 2/10 prostate carcinomas. No mutations were found in the p53 gene. Our findings suggest that mutations of the AR gene are relatively frequent in prostate cancer and may have therapeutical significance.