Mutations on X Chromosome Cause Rare Form of Epilepsy
A rare form of epilepsy called double-cortex syndrome is caused by mutations on a gene located on the X chromosome, according to new research by Susanne Bechstedt and Gary Brouhard of the Department of Biology at McGill University, who discovered how the mutations cause a malformation in the human brain.
Double cortex syndrome is a congenital brain abnormality primarily affecting females that results from an abnormal migration of neurons during development of the cortex, according to the National Institutes of Health. The name double cortex comes from the appearance of an extra layer of neurons (nerve cells) that are under the normal gray matter of brain cortex.
Like Us on Facebook
Bechstedt and Brouhard used an advanced microscope to observe a protein known as doublecortin, which help brain cells build a set of pole-like microtubules which act as a 'skeleton' for the cell. A malfunction in the protein would stop the cells from building a normal structure that would allow it to crawl and migrate.
Under usual circumstances, new brain cells are developed deep within the brain, near the center. And as a baby develops in the uterus, the cells crawl out of the pocket where they formed and migrate outward to the edges of the brain. This outer layer creates the cerebral cortex, where higher-level thinking and cognition are rooted.
The team found that in order for doublecortin proteins to help build the cell skeleton, they need to act as a team. The disease-causing mutations on the X chromosome prevent the proteins from working together, stopping brain cells from building a proper 'skeleton' and resulting in a rare form of epilepsy.
According to the World Health Organization, the cause of epilepsy is only known in 30 per cent of cases, and this new understanding may help researchers develop future therapies.
"This discovery has implications for treatments for a range of conditions, from other forms of epilepsy to spinal cord injuries," said a statement from the university. In each of these types of conditions, therapies are increasingly directed at triggering brain cells to extend their skeletons-for example when re-growing a nerve ending past the site of a wound in the spinal cord, reports Futurity.org.
© 2012 iScience Times All rights reserved. Do not reproduce without permission.