Mutation of the p53 gene, which plays an important role in the genesis of diverse human cancers, was investigated in 23 surgical specimens of human renal cell carcinoma using the polymerase chain reaction single-strand conformation polymorphism method of analysis. Only one of the 23 tumors (4.3%) carried a mutated p53 gene, which was present in exons 7-8. Direct DNA sequencing confirmed a point mutation at codon 276 (GCC to CCC) resulting in a substitution of alanine for proline. No specific clinicopathological characteristics were observed in the case with the p53 gene mutation in human renal cell carcinoma. These observations suggest that mutation of the p53 gene is rare and thus does not contribute significantly to the genesis of this tumor.