Retinitis pigmentosa (RP) refers to a group of inherited disorders that cannot be prevented and that slowly leads to the degeneration of part of the retina, primarily the photoreceptors. There is no known cure for RP, which will eventually lead to blindness.

The retina lines the interior surface of the back of the eye. The retina is made up of several layers. One layer contains two types of photoreceptor cells referred to as the rods and cones. The cones are responsible for sharp, central vision and color vision and are primarily located in a small area of the retina called the fovea. The area surrounding the fovea contains the rods, which are necessary for peripheral (side) vision and night vision (scotopic vision). The rod and cone photoreceptors convert light into electrical impulses and send the message to the brain via the optic nerve where the image...