Human genome: A virus has been ‘fossilised’ in our DNA for 106 million years

The remnants of a virus that plagued our mammal ancestors during the age of the dinosaurs have been found lurking in our genomes



Life



18 February 2022

An artist's impression of prehistoric mammal from the early Cretaceous period

An artist’s impression of prehistoric animals from the early Cretaceous period

MARK P. WITTON/SCIENCE PHOTO LIBRARY

Around 106 million years ago, the DNA of a virus somehow got integrated into the genome of one of our mammal ancestors. Two million years later, something similar happened again with a closely related virus. Now, the ancient remnants of those viruses have been found inside our cells.

“It’s kind of hiding in plain sight in the human genome,” says Aris Katzourakis at the University of Oxford.

These two viral “fossils” are some of the oldest ever discovered, and possibly …