[Evaluation of genetic pattern of non-tuberculosis mycobacterium using VNTR method]

ABSTRACT

Epidemiological studies of Non-tuberculosis Mycobacterium is important because of the drug resistance pattern and worldwide dissemination of these organisms. One of genetic fingerprinting methods for epidemiological studies is VNTR [Variable Number Tandem Repeat]. In this study genetic pattern of atypical Mycobacterium was evaluated by VNTR method for epidemiologic studies. 48 pulmonary and non pulmonary specimens separated from patients with the symptoms of pulmonary tuberculosis [PTB] and identified as Non-tuberculosis Mycobacteriumby phenotypic and PCR-RFLP methods were selected for this study. Clinical samples and their standard strains were evaluated according to VNTR pattern using the 7 genetic loci including ETR-B. ETR-F. ETR-C. MPTR-A. ETR-A. ETR-E. ETR-D. The results of VNTR method showed that none of the 7 loci had any polymorphism in the standard strains of atypical mycobacterium. Some of these variable number tandem repeat in 42 clinical samples of non-tuberculosis Mycobacterium were polymorphic while the PCR product [for any loci] was not found in the remaining 6 specimens. Although the used genetic loci of this study were suitable for epidemiological studies of Mycobacterium tuberculosis, these loci were not able to determine the diversity of genetics of non-tuberculosis Mycobacterium Therefore, it seems necessary that other loci be studied using VNTR method: