Researchers link ancient virus to brain development differences

Researchers at Lund University in Sweden have identified an ancient viral infection that may contribute to the neurological differences between humans and chimpanzees. The virus, identified as PTERV1, belongs to a family capable of inserting genetic material into host cells, which can then be passed down through generations.

In chimpanzees, a specific viral sequence is located near the LINC00662 gene. While this gene is active during the early stages of human brain development, it remains silent in chimpanzees. Using CRISPR technology to remove the viral sequence from chimpanzee cells, researchers successfully reactivated the gene.

Further experiments using brain organoids—laboratory-grown tissue models—showed that when the LINC00662 gene is deactivated in human brain models, the activity of genes responsible for nerve cell formation and connectivity decreases. This suggests the viral trace plays a significant role in suppressing gene expression in chimpanzees.