Improving gene therapy for eye diseases

Scientists have found lab virus that may improve gene therapy for retinal diseases Researchers have developed a less invasive technique that delivers genes across the retinas of mouse and monkey eyes. With further development , the method might be used in people to treat inherited diseases that cause the retina to degenerate and impair sight.
The retina is the light-sensitive tissue at the back of the eye. It converts light into electrical impulses that are sent to the brain through the optic nerve, allowing us to see.
Certain inherited diseases, such as Leber congenital amaurosis (LCA), cause the retina to degenerate and lead to blindness. Scientists have made progress using gene therapy to treat these eye diseases, and several clinical trials are underway. However, the current therapies require inserting a needle through the retina and injecting the engineered virus behind the retina. The procedure can disrupt fragile diseased retinas and delivers the therapy to only a limited region.
A research team led by Drs John G. Flannery and David V. Schaffer at the University of California, Berkeley, set out to develop an improved approach. The virus typically used for gene therapy in the eye is adeno-associated virus (AAV). This harmless virus can’t normally get through the layers of retinal cells to reach affected photoreceptor cells when injected into the vitreous humor — the more easily accessible gel-like fluid at the center of the eye. The scientists devised an approach to engineer variants of the virus that could get through the retina's layers.