Genetic characterisation of Felis catus papillomavirus type 7, a rare infection of cats that may be associated with skin cancer.

Six Felis catus papillomavirus (FcaPV) types have been fully sequenceed from domestic cats including some that have been associated with the development of neoplasia. A sequence from a novel FcaPV type was amplified from a basal cell carcinoma that contained unusual histological evidence of PV infection and intense p16 protein (p16) immunostaining. The entire 7467 bp genome was amplified using 'outward facing' primers. The PV was designated FcaPV7 and contained putative coding regions that were predicted to produce five early proteins and two late ones. The ORF L1 showed 77% similarity to that of FcaPV6. As the novel PV also showed greater than 60% similarity to three other feline Tau-PV types, FcaPV7 is proposed to be classified within this genus. Specific primers were designed but did not amplify FcaPV7 DNA from any of 60 samples from the mouth and skin of cats. FcaPV7 appears to rarely infect cats. However, FcaPV7 may be associated with skin cancer in this species.