Researchers have found that the lentiviruses, a leading cause in a variety of chronic diseases including the deadly HIV/AIDS in humans, is 60 million years old.
There are millions of people worldwide who are affected by the human immunodeficiency virus (HIV), which causes acquired immunodeficiency syndrome (AIDS) in humans.
To better understand its origin, researchers have been looking at imprints left by related viruses in other animals. Until recently, the oldest known lentiviral lineages - in lemurs, rabbits and ferrets - have been found to date back to 3-12 million years ago.
Researchers led by Daniel Elleder from the Czech Academy of Sciences used genomic data from the exotic Malayan flying lemur (colugo) to uncover the oldest lentivirus ever identified, whose first emergence may date to as early as 60 million years ago.
Three samples of colugo genomic DNA containing lentiviralremnants were sequenced and ancient viral genomes were reconstructed and analysed.
"We hope that our findings will allow virologists to better understand how lentiviruses evolved and how their hosts developed defenses against them," said Elleder. In future studies, the team wants to follow the timeline even deeper into the past by surveying a broad spectrum of animals, hoping to identify more pieces of the puzzle of lentivirus evolution.
The findings were published in the journal Molecular Biology and Evolution.
(With agency inputs)