Figure 2: Minimum spanning tree of 67 French B. anthracis strains belonging to the B.Br.CNEVA canSNP lineage

Minimum spanning tree of 67 French B. anthracis strains belonging to the B.Br.CNEVA canSNP lineage (obtained with BioNumerics 6.6 from Applied Maths). Data are based on 345 chromosomal SNPs (A), 14 pXO1 SNPs (B) and 15 pXO2 SNPs (C). The geographic clustering of the French strains is color-coded: Alps in green (34 strains), Pyrenees in purple (9 strains), Massif Central in red (18 strains) and Saône et Loire department in yellow (6 strains). The diameter of each circle varies according to the number of isolates having the same genotype. The length of each branch is proportional (logarithmic scale) to the number of SNPs identified between strains. Indicated in red are the position and name of four French canSNPs described in this study. Based on a parsimony approach, the tree size is 352, i.e. it contains approximately 1.98% of homoplasia. Concerning the plasmids, the tree sizes are 14 and 15 for pXO1 and pXO2, respectively, i.e. it contains no homoplasia.