Phylogenetic tree of SGA-derived env gene nucleotide sequences from the challenge stock, vaccinated breakthrough infections, and unvaccinated control infections. A Neighbor-joining phylogenetic tree was created from complete env gene nucleotide sequences using a consensus approach in Geneious R6 v6.1.4 and annotated in Figtree v.1.4.0. The SIVmac239 env gene sequence was used as an outgroup. The horizontal bar shows the scale of genetic distance. Colors in the key indicate the vaccine or control group of the animal from which the sequences were derived. Challenge stock sequences and the SIVmac239 reference sequence are shown in black. Sequences by vaccination groups are as follows: blue, DgDgMM—RTs10, RRa11; green, MMM—RQh11, RLk11, RVc11, RLi10; orange, controls—Rha11, RIi11, RSo11, RLj12; purple, D40LD40LMM—GL08, FR95, GC66, FP36; red, DDMM—RQw9, RJn11, RTi10, RJf11.