Researchers Find Gene Responsible For Brain Size

"identified a gene mutation responsible for a severe brain defect, a discovery that sheds some light on how the brain has evolved."

"There's a significance here for prenatal diagnosis," he said, adding that a detection of the gene mutation could signal the risk of the brain defect. "Secondly, we're making headway into how the human brain develops."

And that, he said, could lead to better treatment for other neurodegenerative disorders such as Parkinson's disease and Alzheimer's disease.

The findings also could shed some light on the many questions that remain about the brain. Gunel said the degree to which the mutation reduced the brain size suggests that the gene also plays a major role in how the human brain has evolved. The human brain has grown very fast in 5 million years, he said, and has tripled in weight.