Retinitis pigmentosa, a blinding eye disease that is caused by the same genetic defect in both dogs and humans, was successfully corrected by a University of Pennsylvania research team that used gene therapy in afflicted dogs. The retinitis pigmentosa cure holds promise for eventual treatment in humans as well. Both humans and dogs can contract X-linked retinitis pigmentosa (XLRP), a disease that is caused by abnormalities in the RPGR gene. Approximately 100,000 people in the United States suffer with retinitis pigmentosa, a term that refers to a group of inherited eye diseases that cause degeneration of the retina.

http://www.emaxhealth.com/1275/retinitis-pigmentosa-cure-found-using-gene-therapy-dogs