Molecular typing of the Mycobacterium tuberculosis strains circulating in central Russia: efficiency of spoligotyping and VNTR-MIRU

Current problems of molecular epidemiology of the Mycobacterium tuberculosis strains circulating in Samara Region, Russia are discussed. A total of 190 isolates of Mycobacterium tuberculosis were typed using two PCR-based molecular methods. The cultures were isolated from civil and prison patients with pulmonary tuberculosis recruited from different tuberculosis institutions across the Samara region. The usefulness of spoligotyping and 15-locii VNTR-MIRU was assessed for genotyping of Mycobacterium in population with high prevalence of Beijing strains (67.9%) using statistical analyses that included calculation of Hunter-Gaston index. The VNTR-MIRU method was demonstrated to be more efficient and was characterized by higher discrimination (index 0.747) compare to spoligotyping (index 0.572). VNTR-MIRU loci 10, 26, 31, 39, 40 and ETR-A were mostly polymorphic and therefore recommended for use in screening. It could be performed by manual electrophoresid, provided that automated sequencing is not available.