We have analysed the DNA of peripheral blood leukocytes (PBL) from 55 melanoma patients and 53 healthy individuals and failed to find any significant association between melanoma and rare HRAS1 alleles defined by MspI/HpaII digestion. However, the analysis of the same DNAs for a different polymorphism based on the presence of additional TaqI sites in the variable tandem repeat region of HRAS1 showed that the total frequency of a group of allelic variants, named Tp, was significantly higher in melanoma patients than in normal donors.