Strain Diversity of Mycobacterium tuberculosis Isolates from Pulmonary Tuberculosis Patients in Afar Pastoral Region of Ethiopia
Figure 1
A minimum spanning tree (MST) illustrating evolutionary relationships between the M. tuberculosis spoligotypes (a) and various parameters studied such as ethnicity of patients (b), HIV serology (c), occupation (d), and residence (e). Note that the MSTs were constructed using BioNumerics 6.6 on all spoligotypes (). The phylogenetic tree connects each pattern based on degree of changes required to go from one allele to another. The structure of the tree is represented by branches (continuous versus dashed and dotted lines) and circles representing each individual pattern. Note that the length of the branches represents the distance between patterns while the complexity of the lines (continuous, gray dashed, and gray dotted) denotes the number of allele/spacer changes between two patterns: solid lines, 1 or 2 or 3 changes (thicker ones indicate a single change, while the thinner ones indicate 2 or 3 changes); grey dashed lines represent 4 changes; and dotted lines represent 5 or more changes. The size of the circle is proportional to the total number of isolates in our study, illustrating unique isolates (smaller nodes) versus clustered isolates (bigger nodes). The colour of the circles indicates the phylogenetic lineage to which the specific pattern belongs.
