Indigenous populations in Ecuador adapted to TB long before Europeans arrived

The indigenous population of modern-day Ecuador adapted to tuberculosis bacillus several thousand years before the arrival of Europeans, scientists at Emory University have found.

Researchers previously found evidence of the tuberculosis pathogen in the bones of Andean mummies dating back 1,400 years, contradicting some theories that tuberculosis did not exist in South America before the arrival of Europeans 500 years ago, according to an article published in the journal iScience.

Complete genome sequencing of blood samples from 15 modern indigenous people living at altitudes of more than 2,500 meters in several different provinces of Ecuador revealed biomarkers that are commonly present in people with active TB infection. Biomarkers associated with adaptation to hypoxia or low blood oxygen levels as a result of living at high altitude were also found.

Given the presumed timing of gene selection that promotes adaptation, the indigenous peoples of Ecuador may have adapted to Mycobacterium tuberculosis three thousand years before the arrival of Europeans. In addition, a population collapse coinciding with the arrival of Europeans has been found to be more severe than in other regions of the Andes.

Follow NEWS.am Medicine on Facebook and Twitter