Figure 2.

Phylogenetic trees of four domains of the MLV genome. (a) RTpol, (b,c) the env and U3-LTR enhancer substitutions in AKR6, (d) the 5’ VRA-containing end of env. The percentage of trees in which the associated taxa clustered together is shown next to the branches. The trees are drawn to scale, with the branch lengths measured in the number of substitutions per site. Red arrows identify AKR40 and AKR6 MLVs, and green arrows identify AKR6-related PCR products or mined sequences from the AKR/J genome. All of the Xmvs, Pmvs, and Mpmvs are from the B6 reference genome.