Epidermodysplasia verruciformis (EV) is an extremely rare disorder of warts, the pathogenesis of which is poorly elucidated. Individuals with EV have a severe and apparently congenital susceptibility to infection with HPV that may be inherited in an autosomal recessive fashion. EV is clinically characterized by widespread warts that appear in childhood— typically flat warts as well as lesions that are scaly, red/brown macules— which do not revert and often develop into skin cancers. The HPV strains specific to the scaly (scary!) warts that characterize EV are HPV-5 and HPV-8.
Image above: An example of the unique warts seen in patients with EV.
NOT FOR THE QUEASY... A video of a man with extreme case of EV
Individuals with EV are usually infected with several types of HPV, while many healthy individuals without EV harbor the strains of HPV (5 and 8) that are specifically associated with EV. This means there is something very special about these EV individuals that makes them uniquely susceptible to infection with HPV. By studying the genetics underlying families with a history of EV, scientists may be able to clarify what protein products are intimately linked with the resistant HPV lesions. Put in more general terms, in order to develop ways to treat HPV infection, understanding the molecular pathogenesis of the most extreme cases of infection will be invaluable for developing interventions. Currently two genes (EVER1 and EVER2) at the loci 17q25 are being investigated for their role in what appears to be inherited EV.