Beijing family Mycobacterium tuberculosis isolated from throughout Japan: phylogeny and genetic features.

To estimate the current population genetic structure of Mycobacterium tuberculosis in Japan, phylogenetic traits were analysed for 237 Beijing family strains isolated from tuberculosis patients throughout the country. Unlike previous reports from other countries, the ancient Beijing sublineage was predominant throughout Japan. Clustering analysis based on JATA-VNTR (Japan Anti-Tuberculosis Association variable numbers of tandem repeats), a specialised set of VNTR for the discrimination of Japanese M. tuberculosis strains, revealed high similarity of the modern Beijing sublineage strains, irrespective of their geographic origin. JATA-VNTR might be useful for the phylogenetic classification in populations where ancient Beijing strains are frequently isolated.