Gene hunt in dyslexia

Scool? Skuul? Or perhaps shcool? The beginning is a delicate time – especially in reading and writing. Twisted letters or other beginner´s mistakes disappear quite fast as learning progresses. Nevertheless about four percent of German schoolchildren struggle very hard with written words. What is the cause for such a reading and writing disorder called dyslexia? "Dyslexia is not a matter of low intelligence. It is mainly caused genetically, as twin-studies have shown," explains Arndt Wilcke, scientist at the Fraunhofer Institute for Cell Therapy and Immunology (IZI) in Leipzig. Relief could be rendered by a special support for affected children: the German free state of Saxony, for example, maintains classes for dyslexics, beginning with third grade of elementary education. Usually, the disorder is not noticed before the children learn to read and to write at the age of six to eight, but the largest part of speech development is already completed by this time. An accepted thesis is: the earlier a disposition to dyslexia is detected, the better are chances of success for remedial therapy. Supported at kindergarten age, most predisposed children learn reading and writing quite successfully. Scientists at the IZI now try to improve the early discovery of dyslexia. "We are trying to find out which genes cause the disease. A predisposition to dyslexia could be detected by a genetic test to support affected children appropriately at a very early age," says Wilcke. The hypothesis of the IZI scientists is: during brain development at the embryonic stage nerve cells are migrating to their designated positions routed by specific genes. If these are defective the nerve cells do not go far enough or to the wrong places. This could be a cause for dyslexia. Evidence for responsible "dyslexia genes" is already existing. The first steps towards a genetic test have been taken, but more time will be needed to reach this aim – five years would be a realistic guess for Wilcke.

Source: Fraunhofer-Gesellschaft