[Genotyping of Mycobacterlum tuberculosis. An overview of the major research techniques (Part II)]

At present, molecular typing methods of Mycobacterium tuberculosis have become increasingly integrated into the epidemiological studies of tuberculosis. Molecular typing is a process of discriminating between strains of tubercle bacilli, based on the detection of genomic DNA polymorphisms, most frequently associated with repetitive DNA elements. The ability to assess the inter-strain genetic relationships provides a powerful means of resolving a number of epidemiological issues, such as tracing of chains of transmission, determining sources of infection, differentiating recent transmission from reactivation and reinfection from relapse or treatment failure, detecting laboratory cross-contaminations, monitoring the geographic distribution and spread of particular genetic strains (including those of special epidemiological importance), or investigating the evolution of M. tuberculosis. In this review, some major techniques used for genotyping of M. tuberculosis were summarized, as well as selected examples of the application of molecular epidemiological studies to the clinical practice.