Comparison of two molecular diagnostic methods for identifying Beijing genotype of Mycobacterium tuberculosis

Abstract

Background and Objectives: The Beijing family of Mycobacterium tuberculosis has been identified as a severe pathogen among this species and found in many clinical isolates during the last decade. Early identification of such genotype is import- ant for better prevention and treatment of tuberculosis. The present study performed to compare the efficiency of Real-Time PCR and IS6110-Based Inverse PCR methods to identify the Beijing family.

Materials and Methods: This study was carried out on 173 clinical isolates of Mycobacterium tuberculosis complex in Golestan Province, northern Iran. DNA extraction performed by boiling and determining the Beijing and non-Beijing strains carried out using Real-Time PCR and IS6110-Based Inverse PCR.

Results: In both Real-Time PCR and IS6110-Based Inverse PCR method, 24 specimens (13.9%) of the Beijing family were identified and the result of the IS6110-Based Inverse PCR method showed that all the Beijing strains in this region belonged to the Ancient Beijing sub-lineage.

Conclusion: Although the efficacy of the two methods in the diagnosis of the Beijing family is similar, the IS6110-Based Inverse PCR is more applicable to the ability to detect new and old Beijing family.