TB Genotyping

Updated July 29, 2021

What is TB Genotyping?


TB genotyping is a laboratory-based approach used to analyze the genetic material (e.g., DNA) of Mycobacterium tuberculosis, the bacterium that causes TB disease. The total genetic content is referred to as the genome. Specific sections of the M. tuberculosis genome form distinct genetic patterns that help distinguish different strains of M. tuberculosis. TB genotyping methods have changed over time with advances in laboratory technology.

Why do we use TB Genotyping?

TB genotyping results, when combined with epidemiologic data, help identify persons with TB disease involved in the same chain of recent transmission. TB genotyping:

  • Helps distinguish between persons whose TB disease is the result of TB infection that was acquired in the past, as compared to recently or newly acquired infection with development of TB disease,
  • Can add value to conventional contact investigations,
  • Offers a powerful tool to help direct the application of appropriate resources, since TB prevention and control efforts directed at preventing TB transmission are fundamentally different from efforts to prevent reactivation of latent TB infection, and
  • Allows us to monitor our progress toward eliminating TB transmission more accurately.