Intelligence Determined By Brain Thickness Gene
Scientists have discovered a gene linking brain structure to intelligence.
Previous studies revealed that the thickness of the cerebral cortex, the outermost layer of the human brain known as 'grey matter' plays an important role intellectual ability. After analyzing DNA samples and MRI scans of 1,583 healthy 14-year-old teenagers who underwent a series of intelligence tests, scientists found a gene that links the thickness of grey matter to intelligence.
"We wanted to find out how structural differences in the brain relate to differences in intellectual ability. The genetic variation we identified is linked to synaptic plasticity - how neurons communicate. This may help us understand what happens at a neuronal level in certain forms of intellectual impairments, where the ability of the neurons to communicate effectively is somehow compromised," lead author Dr. Sylvane Desrivières, from King's College London's Institute of Psychiatry, said in a news release.
"It's important to point out that intelligence is influenced by many genetic and environmental factors. The gene we identified only explains a tiny proportion of the differences in intellectual ability, so it's by no means a 'gene for intelligence'," Desrivières added.
The findings revealed that teens carrying a gene variant that correlated with a thinner cortex in the left cerebral hemisphere scored lower on intelligence tests. Researchers explain that the genetic variation affects the expression of the NPTN gene, which affects how neurons communicate. Researchers said that latest findings suggest that differences in intellectual abilities can result from the lower activity of the NPTN gene in the brain's left hemisphere.
While the genetic variation found in the study only accounts for 0.5 percent of the total variation in intelligence, researchers said that the findings might provide insight into biological mechanisms underlying psychiatric disorders like autism and schizophrenia.