Experts Cure Patients Blind from Birth

Scientists have taken a major step towards curing blindness recently, when they managed to devise a method that allows patients suffering from the rare, inherited form of blindness known as Leber congenital amaurosis to see light for the first time in their lives. People born with the disease are completely blind since birth, on account of the fact that the photo receptors in their eyes feature an abnormally-expressed protein, which significantly impairs their sensitivity to light. The achievement also seems to highlight the fact that the brain may have the ability to get accustomed to a new sense, in this case vision, even if it never experienced it before.

The new study was conducted on three volunteers, all blind from birth. In just three months of treatment, they reported starting seeing faint lights, which got even brighter after more time. The therapy consists of injecting a functional copy of the abnormal protein into the eye of the patients, over a portion about 8 to 9 millimeters in diameter. In a study published late last year, the University of Pennsylvania in Philadelphia (UPP) team that oversaw the study reported outstanding success with all of their three volunteers, Technology Review notes.

Now, more than one year later, the scientists have the pleasure to announce that their previous results have remained stable, and no visible changes for the worse occurred. The new results are detailed in a scientific paper, published in the latest issue of the journal Human Gene Therapy. In a second paper, which appears in a letter to the New England Journal of Medicine, the team even reports that outstanding changes for the good appeared. “It was unexpected because the major improvement of vision had occurred within weeks after the treatment,” says UPP researcher Artur Cideciyan, who oversaw last year's study.

“It's very encouraging. The formation of almost another vision center has implications as we go forward for patients with congenital blindness. They might not be able to use their normal fovea, but they might be able to develop a new center of vision,” adds University of California in San Diego (UCSD) ophthalmologist Kang Zhang. He is also the director of the UCSD Institute for Genomic Medicine. Zhang was not involved in the recent scientific papers. The study “means that for congenital or childhood blindness, there is the potential to at least stabilize, if not improve, visual function,” Zhang concludes.