Retinitis pigmentosa

Retinitis pigmentosa (RP) is an eye disease affecting the retina.  The retina has rod-shaped cells that are responsible for night vision and seeing in dim light, while cone-shaped cells are responsible for color vision and seeing in bright light.  RP is a hereditary, progressive disease that primarily reduces the function of the rod-shaped cells, eventually leading to severe vision loss.

RP is a particularly devastating disease because onset can begin before age 10, and there is no scientifically validated treatment or cure.  Onset almost always begins by age 30, and many patients experience severe vision loss within fifteen years of onset.  RP affects 50,000 to 100,000 people in the U.S., making it one of the rarest but most severe eye diseases we face.  RP is a variant of Usher’s Syndrome, an inherited condition that includes congenital hearing loss and progressive vision loss by RP.

Limited scientific data suggests that vitamins A and E can slow the progression of RP, but current efforts are largely directed towards early detection so the patient can prepare for limited vision in the future.  Several research groups are also working on retinal implants that might restore limited light perception and the ability to see shadows and shapes, but there is no indication that any of these implants will work.  Finally, scientists are closer to identifying the various genetic defects that cause RP, creating a starting point for genetic screening and potentially for genetic engineering.