Phylogeny based on SNPs and the geographic distribution of 102 isolates of <i>Y</i>. <i>pestis</i> in Qinghai Plateau.

<p>(A) Minimum spanning tree (MSTree) based on 25 SNPs. The dotted-line circle represents the most recent common ancestor (MRCA) of <i>Y</i>. <i>pestis</i>. Colored circles indicate the non-dominant groups of <i>Y</i>. <i>pestis</i> and the white circle indicates the dominant group identified in Qinghai Plateau. The numbers on the branches indicate the SNP distance between nodes. It is important to note that the SNP distance in the MSTree does not represent the actual genetic distance between groups, because only a limited number of SNP loci were selected to be used in the analysis. The number of isolates in each group is indicated within each circle. (B) Geographic distribution of SNP lineages in Qinghai Plateau. Colors of circles correspond to the colors of SNP groups in the MSTree. The five-pointed star marks the capital city of Qinghai province. All of the maps used this paper were created with ArcGIS software based on the public geographical data downloaded from OpenStreetMap (<a href="http://www.openstreetmap.org/" target="_blank">http://www.openstreetmap.org/</a>).