HPV5b variant in a neoplastic lesion of an Italian patient affected by epidermodysplasia verruciformis

Epidermodysplasia verruciformis (EV) can be defined as a genetic disorder that determines a lifelong infection of the skin by human Papillomaviruses (HPV). The benign lesions contain different HPVs; whereas in the tumors HPV types 5, 8, and, much less frequently, types 14, 17, 20 and 47 can be detected. Variants of HPV5 have been recognized on the basis of the genetic heterogeneity of the E6 open reading frame. We report a typical case of EV in which the presence and expression of the HPV type 5 were clearly detectable. Direct sequence analysis demonstrated a perfect homology with the sequence of the HPV5b variant. This variant was first isolated in a Japanese patient and thereafter in a Polish one. Its presence in the Italian patient indicates that the same variant can be detected in different geographic areas and therefore that some cellular genes may exert a selection pressure so strong as to induce the emergence of this stable HPV5b infectious variant.