In palaeomicrobiology, the DNA most frequently extracted is from the pathogen Mycobacterium tuberculosis, commonly known as tuberculosis or TB. TB has afflicted humans for at least 8,000 years. One of the first studies to extract pathogen DNA from archaeological specimens demonstrated M. tuberculosis DNA in a 1,000-year-old Peruvian mummy, proving that tuberculosis existed in pre-Columbian South America. The investigators used polymerase chain reaction (PCR) to amplify IS6110, a short DNA tag derived from the M. tuberculosis genome. IS6110 still remains a means for detecting M. tuberculosis DNA in ancient samples.
Did you know? Analysis of ancient M. tuberculosis DNA suggests that humans infected their livestock with TB during domestication, instead of the other way around as traditionally believed.