Bovine papillomavirus type 4 DNA isolated from a skin lesion in a steer

A lesion on the head of a steer, defined histologically as an epithelial papilloma, yielded DNA which did not hybridise with any of the bovine papillomavirus DNAS usually associated with the formation of skin lesions, DNA from the lesion did hybridise with DNA from bovine papillomavirus 4, even under stringent conditions, and contained a sequence that could be amplified by polymerase chain reaction with primers specific for that virus, Bovine papillomavirus 4 had previously been isolated only from lesions of the upper alimentary canal.