Phylogeny and polymorphism in the E6 and E7 of human papillomavirus: alpha-9 (HPV16, 31, 33, 52, 58), alpha-5 (HPV51), alpha-6 (HPV53, 66), alpha-7 (HPV18, 39, 59, 68) and alpha-10 (HPV6, 44) in women from Shanghai

Persistent infection with human papillomaviruses (HPVs) has been associated with cervical intraepithelial neoplasia (CIN) and cervical cancer. However, why only a fraction of HPV cases progress to cancer is still unclear. We focused on the heterogeneity, classification, evolution and dispersal of variants for 14 common HPV types in 262 HPV-positive patients with cervical lesions. The and genes of HPV were sequenced and compared with the HPV reference for sequence analysis. Phylogenetic trees were constructed using the neighbour-joining tree method with MEGA 7.0. In this study, 233 and 212 sequences were successfully amplified by PCR, and these sequences were divided into 5 species groups: alpha-9 (HPV16, 31, 33, 52, 58), alpha-5 (HPV51), alpha-6 (HPV53, 66), alpha-7 (HPV18, 39, 59, 68) and alpha-10 (HPV6, 44). The incidence of high-grade squamous intraepithelial lesion (HSIL) in patients infected with alpha-9 HPV was significantly increased compared with other groups (