<p class="first" id="P1">HPV variants from the same type can be classified into lineages
and sublineages based
on the complete genome differences and the phylogenetic topologies. We examined nucleotide
variations of twelve HPV types within the species Alpha-5 (HPV26, 51, 69, 82), Alpha-6
(HPV30, 53, 56, 66), Alpha-11 (HPV34, 73), Alpha-13 (HPV54) and Alpha-3 (HPV61) by
analyzing 1,432 partial sequences and 181 complete genomes from multiple geographic
populations. The inter-lineage and inter-sublineage mean differences of HPV variants
ranged between 0.9%−7.3% and 0.3%−0.9%, respectively. The heterogeneity and phylogenies
of HPV isolates indicate an independent evolutionary history for each type. The noncoding
regions were the most variable regions whereas the capsid proteins were relatively
conserved. Certain variant lineages and/or sublineages were geographically-associated.
These data provide the basis to further classify HPV variants and should foster future
studies on the evolution of HPV genomes and the associations of HPV variants with
cancer risk.
</p>