FIG. 5.

Phylogentic tree analysis. Phylogenetic trees were constructed using the neighbor-joining method based on a 380-bp fragment overlapping the 3′ 150 bp of the vpr gene to the end of the vpu reading frame (A), based on the first 290 bp of the nef coding region (B), and based on the 3′ 320 bp of the nef gene (C). Values at the nodes indicate the percent bootstraps in which the cluster to the right was supported. Bootstraps of 70% and higher only are shown. Brackets on the right represent the major subtype sequences of HIV-1 group M.