A page has turned in the history of retinal degeneration. In an amazing feat of gene therapy, scientists have restored vision in dogs with a rare kind of blindness. The report appeared in the May 2001 issue of the journal Nature Genetics . Shortly after birth, infants with LCA begin to develop unusual eye movements and almost total blindness. Researchers had previously used gene therapy to restore vision in rats with the disorder.
Rats represent one step leading to treatment in humans.
Now that gene therapy has succeeded in larger animals, researchers can start the long process of working with human patients. Progress has been rapid since the gene mutation causing LCA was discovered in 1997. The gene, it was found, is responsible for producing a biochemical substance that is needed to turn light shining onto the retina into an electrical signal to tell the brain what is in the visual field. Scientists hypothesized that vision could be restored if they could replace the defective gene with a healthy gene. Twelve weeks following treatment, physiological tests revealed a remarkable improvement in the functioning of the retina.