Figure 6. Phylogenetic Neighbor-Joining Tree for HIV-1 RT Fragment Sequences Obtained from 43 Individuals.

Individual sequences are color coded, with the colors corresponding to those of original geographic sites on the map of Yunnan (Figure 1). The horizontal branch was drawn in accordance with their relative genetic distances. The vertical lines are present purely for clarity of the tree presentation. The bootstrap values based on 1,000 replicates are labeled on the major branches. The reference sequences for classifying HIV-1 genotypes were included and were originally obtained from the NIH/NIAID–funded HIV Databases.