Abstract
Human papillomavirus type 16 (HPV 16) DNA integrated within the cell DNA in cervical carcinomas is frequently defective, but commonly retains its putative transcriptional control region and E6 and E7 open reading frames (ORFs) intact. One clone of such a partially deleted HPV 16 DNA was tested and found to be transforming for rat 3Y1 cells. The result indicates that HPV 16 DNA containing E6 nd E7 ORFs with the homologous promoter is sufficient for inducing focal transformation of immortalized rat fibroblasts.