Overview
Researchers at Lund University in Sweden have shown that an ancient viral pandemic occurring several million years ago is likely part of the explanation for why human and chimpanzee brains developed differently. The viral event resulted in an ancient virus embedded in chimpanzee DNA switching off a gene that remains active in humans.
Research Context
Humans and chimpanzees share almost all of their genes. Despite this shared genetic baseline, the brains of both species developed along divergent evolutionary pathways.
Findings
The findings indicate that an ancient virus integrated into the chimpanzee genome represses a gene that is functionally active in humans. Researchers trace this genetic mechanism back to a viral pandemic that occurred several million years ago, indicating that viral integration is linked to differential gene activity between the two species.
Why This Matters
The research provides an explanation for how distinct brain development emerged between humans and chimpanzees despite the two species possessing nearly identical genetic codes.