Blind man regains partial vision after optogenetic therapy A new type of gene therapy has helped a man regain some vision after 40 years. The French man, who was diagnosed with retinitis pigmentosa (RP) in his teens, began to show signs of visual improvement a few months after the therapy, and was able to see things like the stripes of a pedestrian crossing, and objects on a table in from of him. 'The findings provide proof of concept that using optogenetic therapy to partially restore vision is possible,' said co-author Professor Botond Roska, from the Institute of Molecular and Clinical Ophthalmology in Basel, Switzerland.