Gene therapy treats blindness in dogs
A common form of blindness has been successfully treated in dogs using gene therapy. The technique, which replaces a faulty gene with a functional one, could be used to restore sight to thousands of people affected by the disease.
Retinitis pigmentosa is a genetic disease affecting the cells at the back of the eye that detect light, called rods and cones. The vision of those affected gets progressively worse, causing tunnel vision, until it is completely lost, usually between their 50s and 60s. There is currently no cure. But in the latest research, the vision of four dogs was restored using the new gene therapy, raising hopes of a human treatment.
The disease is caused by mutations in a gene called RPGR, which stop it functioning properly. To correct the mutation, a normal copy of the gene was injected into the eye. The gene was contained within a special carrier molecule that allowed it to enter cells and swap the two genes. The injections stopped the eye disease in its tracks - preventing the onset of severe symptoms and, to some extent, reversing early signs of damage.
A similar technique, also developed in mice and dogs, to treat a different type of genetic blindness, called Leber's congenital amaurosis, has already been trialled in people with encouraging results. The researchers therefore hope that they will soon see a similar success with their latest discovery.
Please see also the AnimalResearch.info page on research into blindness