Scientists have identified over 500 genes linked to intelligence after comparing DNA variations in more than 240,000 people from around the world.
The study, published in the journal Molecular Psychiatry, sheds new light on the biological building blocks of people's differences in intelligence.
Researchers from Harvard University in the US, University of Edinburgh and University of Southampton in the UK identified 538 genes that play a role in intellectual ability.
They also found 187 regions in the human genome that are linked to thinking skills.
Genes found to be linked to intelligence also appeared to influence other biological processes, researchers said.
Some genes linked to intellectual ability are also associated with living longer, scientists found.
They also found that genes linked with problem solving powers were associated with the process by which neurons carry signals from one place to another in the brain.
Using these genetic discoveries, scientists predicted seven per cent of intelligence differences in an independent group of individuals using their DNA alone.
"Our study identified a large number of genes linked to intelligence," said David Hill from University of Edinburgh.
"We were also able to identify some of the biological processes that genetic variation appears to influence to produce such differences in intelligence, and we were also able to predict intelligence in another group using only their DNA," said Hill.
"We know that environments and genes both contribute to the differences we observe in people's intelligence," said Ian Deary, from University of Edinburgh.
"This study adds to what we know about which genes influence intelligence, and suggests that health and intelligence are related in part because some of the same genes influence them," Deary said....