Origins of Tuberculosis Traced Back to Humans

The origins of human tuberculosis have been traced back to hunter-gatherer groups in Africa, according to a study released Tuesday.

An international team of scientists went against the common belief that tuberculosis originated in animals only 10,000 years ago and spread to humans.

The study which was published in Nature Genetics outlined the strong relationship between the evolutionary history of both humans and TB.

Previous research 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.

The 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.

"We found that 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," said Professor Sebastian Gagneux from the Swiss Tropical and Public Health Institute.

"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," he added.

TB causes more than one million deaths around the world every year.