Molecular typing of Mycobacterium tuberculosis by using double repetitive element- polymerase chain reaction method

Introduction . Tuherculosis is still a major wor ldwide health problem. It is responsible for the death of 3 million people each year. E pidemio logica l stu dies with techniques which a llow differ entia tion of stra ins within th e Mycobactrium tuberculosis (MT) are imp ortan t to limit the disseminati on of the disease . The refore, there is a gr eat need for an improved methods to sub type MT strains by a simp le and ra pid molecul ar finger-printing method by usinug double repetitive eleme nt-polymerase chain reaction (ORE-PCR) an alysis, yield s a unique, str ain -sp ecific pattern of hands. Materials and Methods. MT was ob ta ine d from the national research institute of Tu berculos is and lung diseases. To perform ORE-PCR, the DNA molecules were extracted, then ampilicated with PCR. Amplication prod ucts were ana lyze d by ge l electrophores is on 2% agarose and gen erated pa tt erns com pared with togeth er. Those patterns that ide ntical for two or more str ains among thei r 70 MT, were co nsidered as cluster patt erns. Results. Fo urty-two different patt erns were ob served in the 70 isolat ed cases and an alyzed. The ra te of diversity was 60%, which is the same (approved) as the ot he r studies. Thirty-one (44.3%) of the specimens had unique pattern, a nd 39 (55 .7%) of specimens had strains be longing to on e of th e 11 clusters. The patterns had 1-6 band them a pprov ed the ot her studies. There was no cor relation found among th e sp ecial pa tterns, resistance to ant ituberculosis agents, residan ce, migration, and Iran ian patients. The results are th e same as what is reported in th e literature. Conclusion. The data show th e DRE-PCR method is th e simplest a nd the fa stest way to achieve molecular typ ing of MT in Iran.