Detection of human papillomavirus type 56 DNA, belonging to a mucous high-risk group, in hair follicles in the genital area of a woman no longer suffering from viral warts

BACKGROUND: Human papillomaviruses (HPVs) parasitize human epithelium, but it is not clear where they reside when they do not cause apparent infection. Hair follicles are important candidates as reservoirs. OBJECTIVES: A patient reported previously by us as having perianal warts caused mainly by HPV 56, demonstrated hair follicles in her genital area which bulged a little from the surface and appeared somewhat enlarged. We therefore examined whether DNA of HPV 56, a member of the mucous high-risk group, might be detectable in these structures. METHODS: We obtained plucked hairs and performed an examination by polymerase chain reaction and subsequent reverse-phase dot blot hybridization (PCR-RDBH) and in situ hybridization (ISH). RESULTS: Strong positive signals were obtained not only with PCR-RDBH but also with ISH. CONCLUSIONS: Hair follicles in the genital area might serve as reservoirs for HPVs belonging to the mucous high-risk group.