Molecular Characterization of Mycobacteria Causing Pulmonary Tuberculosis in Gondar, North-West Ethiopia

摘要: Background: In human infections, molecular epidemiological studies have suggested that certain Mycobacterium tuberculosis types can be especially prone to drug resistance acquisition or to global dissemination. Some related types of Mycobacterium tuberculosis also appear to be strongly associated with specific geographic locations. Other Mycobacterium tuberculosis strains, such as the Beijing family are reported more pathogenic. Therefore, this study determined the dominant Mycobacterium tuberculosis spoligotype causing pulmonary tuberculosis in GondarObjectives: the aims of this study was to provide an initial and base-line data on the genetic biodiversity of Mycobacterium tuberculosis strains causing pulmonary tuberculosis in Gondar.Methods: Sputum samples were collected from 116 smear positive tuberculosis patients and decontaminated with N-acetyl-L-cysteine (NALC)/sodium hydroxide. DNA was purified at an elution volume of 100 µl using the QIAamp DNA Mini cube. DNA samples were subjected to 16S rDNA/RD750 real time PCR, RD9 multiplex PCR and spoligotype. For 16S rDNA/RD750 assay, PCRs were carried out in 25 µl volumes containing 20 µl of PCR Master Mix and DNA standard was diluted to 10 7, 10 6, 10 5, 10 4, 10 3 and 10 2 M. tuberculosis genomic DNA genomes/µl. For RD9 PCR assay, eighteen µl of the PCR mix were aliquot into a PCR tubes and 2 µl of the DNA template added to the respective tubes and PCR run with the corresponding PCR program in the thermo cycler. The preparations were subjected to gel electrophoresis and image taken using a 12 bit imaging camera. Spoligotype was run by …