Gene therapy treats epileptic rats
Scientists have cured epilepsy in rats by inserting a special gene into neurons of the brain. It is the first time such a technique has been used to treat the neurological disorder and could, in the future, be an alternative to surgical or medical treatments.
Epilepsy is caused by uncoordinated electrical activity in specific known groups of neurons, which in turn can throw the whole brain into chaos, causing a seizure. About 50 million people have epilepsy worldwide, but only seven in 10 will respond to medicine. The alternatives include surgery to remove the defective part of the brain or electric stimulation to restore normal nerve activity.
Another potential treatment could be gene therapy: by adding a new gene to the defective neurons, doctors may be able to prevent them becoming overexcited. The gene, encoding a protein “gate” involved in controlling electrical current, was targeted to selected neurons of rats using a modified and harmless virus. Once inserted into the genome of the neurons the gene caused over-production of the protein gate. The gate allows ions to escape the nerve and, in theory, this should make it harder for the nerve to build up an electrical charge capable of disrupting other parts of the brain.
Epilepsy was induced in the rats using a toxin injection. A fortnight after the gene therapy, the number of seizures in the rats dropped dramatically and after a month the animals were effectively cured. Control rats that did not receive the therapy continued to have seizures.
Gene therapy is an exciting but very new technique. However, it is already being used in people for other conditions, such as cystic fibrosis. Though this is very promising research, it will be many years before the technique will be advanced enough to test in epileptic patients.