Single Protein Domain May Be Responsible for Our Large Brains

For years, scientists have wondered why the human brain is so much larger and complex than that of other species. According to a new study, it could be that a single protein domain (a specific unit of a protein molecule) may be responsible for this advantage.

Little is known about how the brain evolved, but what scientists do know is that the transition was both rapid and dramatic. The international collaboration of experts behind this research wanted to learn how and why this happened, Science Blog reports.

“This research indicates that what drove the evolutionary expansion of the human brain may well be a specific unit within a protein that is far more numerous in humans than other species,” team leader James Sikela, PhD, explains. He adds that the studied protein domain is called DUF1220.

Humans have the highest DUF1220 count of all animals, at 270 copies. The closest species to our own, the chimpanzee, has 125, while gorillas have 99, and mice 1. “The one over-riding theme that we saw repeatedly was that the more copies of DUF1220 in the genome, the bigger the brain,” the team says.