The Neighborhood Joining phylogenetic tree of HPV-31 variants.

<p>The tree was constructed using HPV-31 variants sequences of partial Long Control Region, E6 and E7 identified in Northern China (NC specimens, N = 6) and variants previously reported in whole genome study (N = 19) <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0099141#pone.0099141-Chen1" target="_blank">[14]</a>. Numbers on the nodes indicated the bootstrap values (1000 replicates) of branches. ^* NC_001527 was the reference sequence of HPV-31 and it was not one of the sequences identified in the current study. ^† The sequence of NC-27H9 was the same as IN221709.