Distribution of IS 6110 thorough the M. tuberculosis genome of the studied strains. (A). The obtained locations of IS6110 of each strain were plotted in M. tuberculosis H37Rv genome and represented in three concentric circles: the blue one corresponds to the IS6110 locations in non-Beijing strains. The red one represents the IS-locations in Beijing strains and the green one corresponds to the locations of IS6110 in GC1237 strain. The general hot-spots of M. tuberculosis are indicated by blue/red arrows, the DK1 region is indicated by green arrow and possible specific hot-spots of Beijing genotype are indicated with black arrows. (B) The IS6110 locations obtained in the 17 Beijing strains were plotted in M. tuberculosis H37Rv genome and represented each one in a concentric circle. The IS6110 locations of GC1237 were included as control. The general hot-spots are indicated by blue/red arrows and with black arrows the IS6110-Beijing-hot-spots.