Nature over nurture? You can predict people’s IQ from a DNA test

Rob Waugh
Intelligence could be measured with a swab of saliva

In a study that’s been hailed as the largest-ever investigation into the genetic basis of intelligence, scientists found they could predict someone’s IQ from their DNA.

Intelligence could be measured from a saliva swab, the University of Edinburgh researchers say.

Researchers found 538 genes linked to intelligence, in a study of 240,000 people.

Previous research suggested that 50-75% of intelligence is inherited, and the rest is related to ‘nurture’ – ie upbringing, education and friendship groups.

Intelligence could be measured with a swab of saliva

Dr David Hill, of the University of Edinburgh said, ‘Our study identified a large number of genes linked to intelligence.

‘We were also able to predict intelligence in another group using only their DNA.’

The study also showed that the same genes which influence intelligence are also linked to other biological processes such as length of life.’


The researchers found that genes linked to intelligence are also linked to a long life – which could explain why intelligent people tend to live longer.

Dr Hill said, ‘“We have shown is that two biological processes neurogenesis, the process by which new brain cells are created, and myelination of the central nervous system are associated with intelligence differences.

‘And some of the genetic variants that are linked with an increase in intelligence are also linked with an increase in life expectancy.’