[Study on epidemiological patterns of Mycobacterium tuberculosis by fingerprinting]

ABSTRACT

Despite the availability of effective anti tubercle chemotherapy for more than 50 years and major advances in the biology of M. tuberculosis, TB remains the leading cause of adult mortality attributable to a single pathogen. The analysis of tuberculosis and tracing of the source of infection require the ability to discriminate among Mycobacterium tuberculosis strain. In present study Restriction Fragment Length Polymorphism [RFLP] analysis was used to study the molecular epidemiology of tuberculosis in Tehran. Mycobacterium tuberculosis isolates from 292 patients with culture positive tuberculosis during 2002-2003. Extraction of bacterial DNA and DNA fingerprinting with RFLP using lS6110 as probe, was performed by standard protocols. The digested DNA is separated according to fragment size on agarose gel by electrophoresis and southern transferred on to a membrane. The DNA probe was labeled with [HRP] and hybridizing to the genomic targets. Among 292 culture M. tuberculosis, 232 [79.4%] belonged to clusters and 60 [21.6%] did not. 39 Drugs resistant M. tuberculosis isolates were examined 33%of these were identical pattern lS6110. 4.9% of the isolates represented the Beijing genotype. Based on the obtained data it appears that tuberculosis among the study population in Tehran mainly from reactivation of latent infection