MUTATION OF THE P53 TUMOR-SUPPRESSOR GENE OCCURS PREFERENTIALLY IN THE CHROMOPHOBE TYPE OF RENAL-CELL TUMOR

Genomic DNA from 30 non-papillary and 20 chromophobe renal cell carcin omas (RCCs), 30 papillary renal cell tumours, and 20 renal oncocytomas was screened for the presence of mutations in exons 5-8 of the p53 tu mour suppressor gene by polymerase chain reaction-single strand confor mation polymorphism analysis and direct DNA sequencing. Mutations lead ing to an amino acid change mere found only in 6 out of 20 chromophobe RCCs. Microsatellite analysis of chromophobe RCCs revealed the loss o f one allele at chromosome 17p in 14 out of 18 informative cases. No m utation of the p53 gene was found in five sarcomatous RCCs or in seven tumours of stage IV. This study shows that mutation of the p53 tumour suppressor gene does not correlate with the specific loss of DNA sequ ences at chromosome 17 in chromophobe RCCs, nor can it be used as a pr ognostic parameter for RCCs in general.