Analysis of Human Papillomavirus 51 (HPV51) Genetic Variations Detected in Women with Cervical Dysplasia

HPV51 belongs to group I high-risk HPV (hrHPV) genotypes with a high prevalence of infection in numerous epidemiological studies, although its occurrence varies across geographical regions. To better understand the presence of variants and genetic variation of HPV51, this study aimed to perform a phylogenetic analysis of the E6, E7 and L1 regions to detect the hrHPV variants circulating in women referred to colposcopy in two different Italian regions (Lombardy and Sardinia). Cervical samples were tested using Anyplex™ II HPV HR Detection. HPV51 positive samples were further analysed using previously described PCR protocols to obtain sequences of E6, E7 and L1. A positivity rate for HPV51 of 7.4% (26/351) and 13.6% (11/81) was found in Lombardy and Sardinia, respectively. The majority (34 out of 35) of the analyzed sequences clustered into the A lineage and only one sequence was grouped into B lineage. L1 capsid gene showed the presence of different mutations but none under positive selective pressure. Three nucleotide polymorphisms T6311G, A6312T and G6313A related to the two aminoacidic mutations V264G and G265S were found among all analysed sequences. This study contributes to implement data regarding the molecular epidemiology of HPV but additional analysis on a larger number of sequences is necessary to better understand the role of HPV variants in cervical lesions development.