FIG. 1.

(a) Diagram of the serial passage of leprosy lesions between SMs and BkMs. (b to d) Phylogenetic relationships between SIVsm strains infecting the SMs involved in serial passage of M. leprae and of BkMs inadvertently infected with SIVsm during the leprosy experiments. The analysis of gag (640-bp) (b), pol (588-bp) (c), and env (396-bp) (d) gene fragments revealed that all these viruses cluster in different SIVsm lineages and that BkMs were infected with the virus strain naturally infecting SMG930, the final SM in the series. Trees were constructed using the neighbor-joining method with 1,000 replicates. The bootstrap values at the nodes represent the numbers of replicates. Only significant values (>750) are shown. Each lineage is shown in the same color: lineage 1, red; lineage 2, violet; lineage 3, green; lineage 4, blue.