Human papillomavirus (HPV) genotype 18 variants in patients with clinical manifestations of HPV related infections in Bilbao, Spain.

Background: Human papillomavirus (HPV) variants differ in their biological and chemical properties, and therefore, may present differences in pathogenicity. Most authors classified variants based on the phylogenetic analysis of L1 region. Nevertheless, recombination in HPV samples is becoming a usual finding and thus, characterizing genetic variability in other regions should be essential.