Scientists have linked more than 500 genes to intelligence in the largest study of its kind.
Researchers compared DNA variants in more than 240,000 people to identify 538 genes associated with intellectual ability.
They also highlighted 187 regions in the human genome, or genetic atlas, linked to thinking skills.
Intelligence genes appeared to influence other biological processes and some were associated with living longer.
Genes involved with problem solving were found to play a role in nerve signals passing from one place to another in the brain.
The findings made it possible to predict 7% of intelligence differences in a group of individuals just by analysing their DNA.
Lead scientist Dr David Hill, from the University of Edinburgh, said: "Our study identified a large number of genes linked to intelligence.
"Importantly, 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."
The scientists gathered data from the UK Biobank, which holds anonymous genetic information on 500,000 people.
Their findings are published in the journal Molecular Psychiatry.