People suffering from choroideremia, a rare degenerative eye disease, may soon have a way of improving their vision by means of gene therapy.
The disease, which affects more males than females, is caused by defects in a single gene on the X chromosome, which leads to blindness, and is estimated to occur in 1 out of every 50,000 people.
Researchers at the University of Oxford, in an early stage clinical trial, used a deactivated virus to safely alter the natural genes by substituting them with billions of healthy, lab-made replacements.
This process helped to restore functionality to photoreceptors within the eye.
At first, only six patients were involved in testing this new method of treatment, with varying levels of visual acuity between them. Improvements were seen across the board, with the greatest advancements in those who had the poorest vision at the beginning of the trial.
Patients starting off with the best vision of the group mostly saw vision improvements in low light environments. The gains in vision were sustained during the follow-up exams, which lasted several months.
This experiment is the first attempt at using gene therapy to target the main light-sensing cells in the retina.
If proven to be successful on a larger scale, it could provide a method of treating many more common causes of blindness that affect the same cells, including retinitis pigmentosa, and macular degeneration.