Genetic diversity and bioinformatic analysis of the HPV-45 L1 gene in Iranian women with normal cytology

Abstract

BackgroundHuman papillomavirus type 45 is a potential risk of 3-9% of cervical cancers in a geographic-dependent pattern but it is uncommon in women with normal cytology. MethodsIn this study, we aimed to investigate the HPV-45 L1 gene to find the predominant variants in women with normal cytology, as a general population. We analyzed the nucleotide and amino acid changes along the L1 gene for embedding in N-glycosylated sites, external surface loops, and for positive/negative selection. ResultsThe B1 sub-lineage was the most frequent variants (40%), followed by each of B2, A1, and A2, accounting for 20%. None of missense variations affected the HPV-45 L1 function or located in the N-glycosylated sites. Three amino acid deletions occurred in the C-terminus and seven codons were under negative selection. Also, four mutations were embedded in the surface loops; N81S in BC loop, I166V in DE loop, and S383G/N and Q392H both in HI loop. ConclusionGiven the importance of HPV-45 and its sub-lineages in developing cervical cancer, a phylogenetic classification of HPV-45 circulating in general population may assist in setting the screening programs, diagnosis methods, and future epidemiological studies.