FIG. 3.

Phylogenetic tree determined from the DNA sequence of the ospC genes of southern and other genospecies strains of B. burgdorferi sensu lato. The UPGMA tree was constructed with PAUP software and is based on a comparison of 344 bp of ospC genes. The tree was compared with the trees produced by neighbor-joining, maximum-likelihood, and parsimony methods with PAUP software. The four methods produced similar results. Scale bar represents calculated distance value. The abbreviations are defined in the legend to Fig. 2. A and E, America and Europe, respectively (these letters indicate the geographic origins of the isolates).