Twenty cutaneous warts from I8 renal transplant recipients (RTR) and a single wart sample from a patient suffering from Hodgkin's disease were screened for the presence of human papillomavirus (HPV) sequences by Southern blot analysis. Thirteen samples were shown to contain HPV DNA sequences, one was identified as HPV-3, two as HPV-4, six as HPV-2 and four were unidentifiable by restriction digest analysis. HPV-3 was identified in the wart sample from the patient suffering from Hodgkin's disease. In the six samples in which HPV-2 was found, the viral genome showed polymorphism for the PvuII and PstI sites. Two PvuII patterns and one PstI pattern are novel.