Gene therapy might lead to blindness reversing: study

LONDON, Oct. 3 (Xinhua) -- Blindness might one day be reversible thanks to gene therapy that can reprogram cells at the back of the eye to become light sensitive, according to a study released on Tuesday by the University of Oxford.

Inherited retinal degenerations such as retinitis pigmentosa can cause a gradual loss of vision and eventual blindness. This is the most common cause of blindness in young people. However, even after a patient's eyesight has been lost to this condition, the remaining cells in the retina that are not light-sensitive remain intact.

A team of researchers at the University used a modified virus to inject a new gene into these cells, which then express a light sensitive protein, melanopsin, in the residual retinal cells in mice which were blind from retinitis pigmentosa.

The mice were monitored for over a year and they maintained vision during this time, being able to recognize objects in their environment which indicated a high level of visual perception, according to the study. The cells expressing melanopsin were able to respond to light and send visual signals to the brain.

"There are many blind patients in our clinics and the ability to give them some sight back with a relatively simple genetic procedure is very exciting. Our next step will be to start a clinical trial to assess this in patients," said Samantha de Silva from the University, who is the lead author of the study.