Origins of TB Traced Back To Humans

Posted on 03 Sep 2013 at 4:57pm

tb

The origins of TB i.e. tuberculosis have been traced back to hunter-gatherer groups in Africa 70,000 years ago, an international team of scientists say.

The research goes against common belief that TB originated in animals only 10,000 years ago and spread to humans. The work, published in Nature Genetics, outlines the strong relationship between the evolutionary history of both humans and TB.

Previous research has indicated that human TB originated about 10,000 years ago in Africa during the Neolithic Demographic Transition (NDT), when the human population was expanding and agriculture was becoming prominent. Researchers combined geographic and genetic data from 259 strains of TB to reconstruct its evolutionary history and compare it to the origins of humans in Africa.

Prof Sebastian Gagneux, from the Swiss Tropical and Public Health Institute, said: “We found that the most basal – the earliest – lineages of TB and humans originated in the same place, in Africa, 60,000 years earlier than what people previously thought.

“What we have done is provide a strong hypothesis to reinforce the idea that TB originally started in humans, and migrated to animals during NDT.”