Imaging Study Produces Genetic Brain Maps

Scientists are finally beginning to understand how common genetic differences among individuals underlie differences in the structures that make up their brains. In the first attempt to actually map these variations, neurologist Paul Thompson and colleagues at the University of California at Los Angeles have discovered that brain structures related to cognitive ability and language seem to be under tight genetic control. The group’s findings, which could help explain how diseases like schizophrenia are passed on, will appear in a report in the December issue of Nature Neuroscience.

To construct their so-called genetic brain maps, the researchers scanned the brains of 20 sets of twins (ten fraternal and ten identical) with magnetic resonance imaging and combined the results to construct an average brain map for each kind of twin. In the brain map of identical twins pictured at the right, for example, brain areas exhibiting more variation appear in blue, whereas those showing less variation are red. These pairs of twins showed almost no differences in the amounts of gray matter in the frontal, sensory-motor and language-related parts of their cortexes. Fraternal twins, who share half of each other’s genes, showed more variation in these structures than did identical twins and less than unrelated individuals did, suggesting that “some areas of the brain are under tight genetic control—language in particular,” Thompson explains. This genetic control may also extend partly to cognitive ability: study participants with more gray matter in the front of their brains scored higher on a common test designed to measure Spearman’s g, which is similar to IQ. “But this is quite a mild correlation,” Thompson says. “You can’t predict an individual’s IQ from a brain scan, and I think that’s quite a relief.”

The kind of brain mapping employed in this study could help scientists determine why dementias such as schizophrenia, which affects the frontal cortex, are often passed down between generations. By “building a mosaic, or jigsaw, which shows each individual part of the brain and to what extent genes influence it,” Thompson says, “we can begin to point to why there’s an inherited risk to brain disease.”—

Media Contact

JR Minkel Scientific American

All latest news from the category: Life Sciences and Chemistry

Articles and reports from the Life Sciences and chemistry area deal with applied and basic research into modern biology, chemistry and human medicine.

Valuable information can be found on a range of life sciences fields including bacteriology, biochemistry, bionics, bioinformatics, biophysics, biotechnology, genetics, geobotany, human biology, marine biology, microbiology, molecular biology, cellular biology, zoology, bioinorganic chemistry, microchemistry and environmental chemistry.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors