Doubled gene for extra smarts Bigger brains may be result of duplicated SRGAP2 gene

摘要

Bigger, better human brains may have been the result of a double dose of a gene that helps brain cells move around. At least twice in the past 3 million years, a gene called SRGAP2 has been duplicated within the human genome, said Megan Dennis of the University of Washington in Seattle. Dennis and her colleagues reported October 13 that extra copies of this gene may account for humans' thicker brain cortex, the gray matter where thinking takes place.