A DNA Clue to Reading Troubles
Scientists have identified the first gene involved in some cases of dyslexia, a learning disorder that affects at least 1 in 25 people. People with dyslexia have trouble with spelling, reading, writing, explaining their thoughts in words, and understanding sounds within words.
Kids with dyslexia often have trouble with reading and explaining their thoughts in words.
Cells in your body contain long molecules called DNA, which provide instructions for making materials called proteins. Roughly speaking, a stretch of DNA that makes a specific protein is known as a gene. If a gene is defective, it could produce the wrong protein and cause something in your body not to work properly.
In their search for genes involved in dyslexia, scientists had previously narrowed their focus to a few stretches of DNA that held tens or hundreds of genes. Within one of those regions, a group of Swedish researchers found a gene mutation in certain members of a Finnish family. The father, who was dyslexic, and his two dyslexic daughters all had a mutation in a gene called DYXC1.
Then, the researchers broadened their study to look at 109 children and adults diagnosed with dyslexia and 195 people without the learning disorder. Results showed that 9 percent of those with dyslexia had the DYXC1 mutation, compared with fewer than 3 percent of the other group. A different kind of DYXC1 mutation appeared in 12 percent of the dyslexic group, compared with only 5 percent of the others. Scientists now have to figure out how the gene and its protein work.
DYXC1 is clearly not the only gene involved in dyslexia, the researchers say. Still, they hope their findings will help doctors diagnose and treat people with the learning disorder.—E. Sohn
Bower, Bruce. 2003. Dyslexia's DNA clue: Gene takes stage in learning disorder. Science News 164(Aug. 30):131. Available at http://www.sciencenews.org/20030830/fob1.asp .
You can learn more about dyslexia at http://kidshealth.org/kid/health_problems/learning_problem/dyslexia.html (KidsHealth for Kids) and http://faculty.washington.edu/chudler/dyslexia.html (Neuroscience for Kids).