'Smart genes' account for 20% of intelligence: study

PARIS – Scientists on Monday announced the discovery of 52 genes linked to human intelligence, 40 of which have been identified as such for the first time. The findings also turned up a surprising connection between intelligence and autism that could one day help shed light on the condition's origins. Taken together, the new batch of "smart genes" accounted for 20 percent of the discrepancies in IQ test results among tens of thousands of people examined, the researchers reported in the journal Nature Genetics says. "For the first time, we were able to detect a substantial amount of genetic effects in IQ," said Danielle Posthuma, a researcher at the Center for Neurogenomics and Cognitive Research in Amsterdam, and the main architect of the study. "Our findings provide insight into the biological underpinnings of intelligence," she said. Most of the newly discovered gene variants linked to elevated IQ play a role in regulating cell development in the brain, especially neuron differentiation and the formation of neural information gateways called synapses.