Restricted structural gene polymorphism in the Mycobacterium tuberculosis complex indicates evolutionarily recent global dissemination.

ABSTRACT: One-third of humans are infected with Mycobacterium tuberculosis, the causative agent of tuberculosis. Sequence analysis of two megabases in 26 structural genes or loci in strains recovered globally discovered a striking reduction of silent nucleotide substitutions compared with other human bacterial pathogens. The lack of neutral mutations in structural genes indicates that M. tuberculosis is evolutionarily young and has recently spread globally. Species diversity is largely caused by rapidly evolving insertion sequences, which means that mobile element movement is a fundamental process generating genomic variation in this pathogen. Three genetic groups of M. tuberculosis were identified based on two polymorphisms that occur at high frequency in the genes encoding catalase-peroxidase and

SUBMITTER: Sreevatsan S 

PROVIDER: S-EPMC23284 | biostudies-literature | 1997 Sep

REPOSITORIES: biostudies-literature