In a significant advance in the study of mental ability, a team of European and American scientists announced on Monday that they had identified 52 genes linked to intelligence in nearly 80,000 people.
Dr. Posthuma wanted to find the genes that influence intelligence.
So scientists turned to what’s now called the genome-wide association study: They sequence bits of genetic material scattered across the DNA of many unrelated people, then look to see whether people who share a particular condition – say, a high intelligence test score – also share the same genetic marker.
As a result, the first generation of genome-wide association studies on intelligence failed to find any genes.
In the past couple of years, larger studies relying on new statistical methods finally have produced compelling evidence that particular genes really are involved in shaping human intelligence.
To her surprise, 52 genes emerged with firm links to intelligence.
Studies like the one published today don’t mean that intelligence is fixed by our genes, experts noted.