Scientists Identify Gene Linking Brain Structure to Intelligence
For the first time, scientists have identified a gene linking the thickness of the gray matter in the brain to intelligence. The study may help scientists understand biological mechanisms behind some forms of intellectual impairment.
The researchers looked at the cerebral cortex, the outermost layer of the human brain. It is known as gray matter and plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. Previous studies have shown that the thickness of the cerebral cortex, or cortical thickness, closely correlates with intellectual ability; however, no genes regulating this feature had yet been identified.
An international team of scientists analyzed DNA samples and MRI scans from 1,583 healthy 14-year-old teenagers, part of the IMAGEN cohort. The teenagers also underwent a series of tests to determine their verbal and nonverbal intelligence.
Sylvane Desrivieres, lead author of the study, said, "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."
She added, "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. …