DNA variants that are bad for health may also make you stupid

What makes some people smarter than others? A genetic analysis of families in Scotland, UK, hints that brainer people have fewer DNA mutations that impair intelligence and general health, rather than having more genetic variants that make them smarter. "This is one of the most exciting studies on the genetics of intelligence I've seen for a while," says Steve Stewart-Williams of the University of Nottingham Malaysia Campus, who was not involved in the work. One implication is that using gene editing to fix the hundreds of mutations that slightly damage people's health would make them smarter as well as healthier. "I think this strengthens the moral case for pursuing genome editing technologies," says ethicist Christopher Gyngell of the University of Oxford.