Fig. 1.

Variability of HDNP loci. Pairwise nucleotide differences of B. burgdorferi HDNPs are shown. Data for some pairs are missing (no vertical bar). (A) HDNPs on the main chromosome. (B) Plasmid HDNPs. Note that most ORFs are polymorphic in two of the three pairwise genome comparisons and varied little in the third pairwise comparison (low vertical bar). BBB19 (ospC), BBA24, and BB0144 stand out as the only ORFs that are significantly (P < 0.001) variable in all three pairwise comparisons. Note the scale difference in the vertical axis between A and B. *, ORFs used in MLST.