London: A single gene may have structured the size and shape of the human brain`s cerebral cortex, the seat of his intellect.
The evolution of the brain`s `thinking` region has triggered some of our greatest achievements from the works of Shakespeare to splitting the atom.
How the human brain has developed has been the subject of much research and controversy.
Now scientists have uncovered evidence that the evolution of the cerebral cortex may have been driven by just one gene, the American Journal of Human Genetics reports.
A study found that mutations in the gene NDE1 caused a congenital condition in which children are born with abnormally small brains. The gene is involved in cell division, according to the Daily Mail.
Offspring from one Turkish and two Pakistani families with the microcephaly disorder had brains just 10 percent of normal size.
They also lacked the normal architecture of the cerebral cortex that is the hallmark of the human brain.
Professor Murat Gunel, from Yale University in Connecticut, who led the research, said: "The degree of reduction in the size of the cerebral cortex and the effects on brain morphology suggest this gene plays a key role in the evolution of the human brain."
"These findings demonstrate how single molecules have influenced the expansion of the human cerebral cortex in the last five million years. We are now a little closer to understanding just how this miracle happens," Prof Gunel added.