Scientists have found more than 50 new genes linked to intelligence. This discovery provides fresh insights into the “genetic architecture of intelligence” and how genes relate to IQ.
The exact percentage of how much of intelligence is inherited is still up for debate, but scientists agree that a large portion of it really does get handed down from parent to child. Therefore, intelligence is based on genetic factors, Newsweek reports.
But intelligence is not just one trait influenced by some genes. It is a complex web made up of hundreds of genes, many of which science still has to identify.
A team of scientists sampled almost 80,000 people to come up with their results. They conducted a large-scale, meta-analysis that factored in several different ways to measure intelligence, along with the participants’ genetic information.
Two kinds of genetic analysis showed different genes relating to intelligence. The first analysis, called a genome-wide association study, revealed 22 genes, 11 of which were new. In the second, genome-wide gene association analysis, 29 new intelligence genes came out.
Most of the genes were found in brain tissue. The researchers wrote,
Pathway analysis indicates the involvement of genes regulating cell development.
Danielle Posthuma from Vrije Universiteit Amsterdam said that the find was unexpected. “I’ve run a lot of genome studies and a lot of the time you don’t find a lot of genes, even though the traits you are investigating are highly heritable. And it’s only if you have a really large sample size that you start to find things.” The discovery was “happily surprising,” though Posthuma added that there are hundreds of genes more they need to find before a complete picture of intelligence can be formed.
The researchers also said that these genes cannot be used to engineer smarter animals, and that doing so would have unintended consequences, either positive or negative.
The team now hopes to identify more genes linked to intelligence, and to conduct more experiments to take a closer look at the genes they have found.
The study was published in Nature Genetics.