Whole genome comparison between all three strains. Pink, blue and green regions are strain-specific sequences of T2Bo, L17 and T strains, respectively. Overlapping area in the center of each Venn diagram represents nucleotide sequences (coding and non-coding) that are shared among all virulent or attenuated strains. Areas shaded in pink, blue and green are strain-specific nucleotide sequences found in T2Bo, L17 and T strains, respectively. Both Venn diagrams are not drawn to scale.