Figure 3. Minimum spanning tree constructed by using single-nucleotide polymorphism (SNP) and variable number tandem repeat (VNTR) polymorphism profiles for Mycobacterium leprae samples from patients and armadillos from the southeastern United States. Each circle represents a single strain genotype of M. leprae. Large circles indicate that >1 sample (number shown) had a common genotype. Values along lines indicate number of differences between allelic profiles. Human and armadillo samples of common SNP subtype 3I-2 are indicated by different colors. Only 2 genotypes were present in >1 sample, and both genotypes were present among armadillos and patients.