Spellbound. Researchers may have identified a gene linked to dyslexia.

Spelling Out the Causes of Dyslexia

Scientists have homed in on a gene that might be involved in dyslexia, a condition that causes difficulty with reading and spelling. The gene has appeared as a suspect before, and researchers hope that the new findings will help them better understand what happens in the brains of people with this condition, as well as provide insights into the workings of language.

Dyslexia afflicts up to 10% of the population, and although those individuals have trouble with reading and spelling, they often have normal or even above-average intelligence. They also use slightly different parts of their brains than the average person does when reading and writing. The condition seems to be at least partly inherited, but it has been a challenge to find any of the genes involved, which are most likely scattered across several chromosomes.

Now, researchers believe that they are one step closer to fingering a possible culprit. Natalie Cope and Julie Williams of Cardiff University in the United Kingdom and their colleagues studied 223 people with dyslexia, as well as their families and 273 controls. The team reports in the current issue of the American Journal of Human Genetics that those with dyslexia had a strong tendency to carry alterations in KIAA0319, a gene on chromosome 6p.

The exact function of the gene remains unclear, however. Unrelated studies have shown that it is turned on in brain and kidney tissues, and there are some hints that it might play a role in helping cells stick together. In addition, Williams says her team has some preliminary evidence that certain versions of the gene may be associated with particularly good reading skills. She believes that tracking down the gene's role in development might not only uncover ways to help slow readers but "might also give insight into how the brain processes language."

Such a gene might influence the migration of cells during brain development, says Anthony Monaco of the Wellcome Trust Center for Human Genetics in Oxford, U.K. Monaco's group has also found strong evidence of alterations in or near the gene in their studies of people with dyslexia, in both the United Kingdom and the United States. "It is exciting," he says, to be zeroing in on a gene for a trait as complex as this one is.

Related sites
Abstract of study
Julie Williams' website
International Dyslexia Association
Dyslexia information from NIH (National Institute of Neurological Disorders and Stroke)