Ancient Gene Unlocks Human Brain Fold Mystery

Chinese scientists have unraveled the mystery behind how an ancient gene regulates the development of brain folds, offering new insights into human brain evolution. The research, published in Nature Genetics, proposes that conserved genes, rather than solely newly evolved ones, play a crucial role.

The study found that the ancient gene CCNB1IP1, expressed even in early primate relatives, significantly increased in expression levels through primate evolution. This rise in expression directly correlates with the degree of cortical folding observed in different species, reaching its peak in the human brain.

Further investigation identified a regulatory sequence, CRE1, responsible for this elevated expression. When introduced into mice, which typically have smooth brains, this gene induced cortical folding. These modified mice also exhibited enhanced learning and memory capabilities in behavioral tests, suggesting a link between brain folding and cognitive function.