The standardized method
to study the polymorphism of IS 6110 was used to characterize 53 isolates of Mycobacterium tuberculosis
obtained during 1991-1992 from 14 regions in Colombia.
In Valle region cluster rate was 25% (4/16). The mean number of IS6110 band was
10 ± 3. Similarity between strains was of 60% in 81% of strains and this
tended to be correlated with geographic origin. For the first time M. tuberculosis
without IS6110 bands in restriction fragment length polymorphism analysis was
found in Colombia. Additional studies are necessaries in order to best characterize
the situation in relation to human immunodeficiency virus epidemic and recent
changes in tuberculosis control program.