Genes which make people intelligent have been discovered and scientists believe they could be manipulated to boost brain power.
Researchers have believed for some time that intellect is inherited with studies suggesting that up to 75 per cent of IQ is genetic, and the rest down to environmental factors such as schooling and friendship groups.
But until now, nobody has been able to pin-point exactly which genes are responsible for better memory, attention, processing speed or reasoning skills.
Now Imperial College London has found that two networks of genes determine whether people areintelligent or not-so-bright.
They liken the gene network to a football team. When all the players are in the right positions, the brain appears to function optimally, leading to clarity of thought and what we think of as quickness or cleverness.
However when the genes are mutated or in the wrong order, it can lead to dullness of thinking, or even serious cognitive impairments.
Scientists believe that there must be a ‘master switch’ regulating the networks and if they could find it, they could ‘switch on’ intelligence for everyone.
“We know that genetics plays a major role in intelligence but until now haven’t known which genes are relevant,” said Dr Michael Johnson, lead author of the study from the Department of Medicine at Imperial College.
“This research highlights some of genes involved in human intelligence, and how they interact with each other.
“What’s exciting about this is that the genes we have found are likely to share a common regulation, which means that potentially we can manipulate a whole set of genes whose activity is linked to human intelligence.
“Our research suggests that it might be possible to work with these genes to modify intelligence, but that is only a theoretical possibility at the moment – we have just taken a first step along that road.”
In the study, published in the journal Nature Neuroscience, the team of researchers looked at samples of human brain from patients who had undergone neurosurgery for epilepsy.
They analysed thousands of genes expressed in the human brain, and then combined the results with genetic information from healthy people who had undergone IQ tests and from people with neurological disorders such as autism spectrum disorder and intellectual disability.
They conducted various computational analyses and comparisons in order to identify the gene networks influencing healthy human cognitive abilities. Remarkably, they found that some of the same genes that influence humanintelligence in healthy people were also the same genes that cause impaired cognitive ability and epilepsy when mutated, networks which they called M1 and M3.
Dr Johnson added: “Traits such intelligence are governed by large groups of genes working together – like a football team made up of players in different positions.
“We used computer analysis to identify the genes in the human brain that work together to influence our cognitive ability to make new memories or sensible decisions when faced with lots of complex information.
“We found that some of these genes overlap with those that cause severe childhood onset epilepsy or intellectual disability.