Unique Human DNA Thought To Have Role In Cortex Development
Scientists from the University of California have found gene HAR1, active in Cajal Retzius neurons, is expressed during early embryonic development at the same time that protein reelin is active. Reelin guides the growth and connections of neurons. Although evidence is not conclusive, the scientists believe it suggests HAR1 is important in the development of the cerebral cortex. As there are few differences between HAR1 in all mammals, excluding humans which shows 18 differences, it is thought that the changes in this gene and its effects has lead to the human brain evolving more than others. Another interesting finding was that the gene does not appear to control production of a specific protein, but modifies the function of other genes and that this modification could be the reason for the rapid evolution of the human brain.