Lund University Research Identifies Gene Silencing by Ancient Virus as Key Difference in Human and Chimpanzee Brain Development

Researchers at Lund University have uncovered significant genetic differences contributing to early brain development variations between humans and chimpanzees, focusing on the LINC00662 gene. Despite the high genetic similarity of more than 96% in protein-coding genes shared by humans and chimpanzees, the LINC00662 gene is active in humans but silenced in chimpanzees due to an ancient viral DNA insertion. Using stem cell-derived three-dimensional brain organoids, the team employed CRISPR-Cas9 technology to remove the viral residue in chimpanzee cells, successfully reactivating LINC00662. Conversely, suppressing this gene in human brain models did not produce noticeable changes, indicating complex regulatory mechanisms are still not fully understood.

This research highlights the crucial role of gene expression regulation, rather than gene sequence alone, in the evolutionary divergence of human brain development.

Postdoctoral researcher Patricia Gerdes emphasized that while these brain organoid models offer valuable insights, further studies are necessary to link these cellular-level findings to actual brain development in living organisms. The study was published in the journal Science Advances, providing a new piece of the puzzle in understanding what genetically distinguishes humans from their closest relatives, the chimpanzees.