Chelsea Lee
Medical Research Editor
WhereismyDoctor.com

Blind See Again with Gene Therapy

March 31st, 2012

A certain type of inherited blindness known as Leber's congenital amaurosis, or LCA, is now on the verge of becoming a reversible condition.

People with LCA are born with distorted vision, and that vision continues to deteriorate until the individual is essentially and sometimes even legally blind. The disease affects a person's vision by attacking the photoreceptors in the eye, and is thought to be the result of a mutated retinal gene.

Exciting new research shows that gene therapy can improve vision destroyed by LCA. Even those who are virtually blind may be able to improve their vision enough to see large objects, read large print, and recognize faces.

The Huff Post reports that three previously blind women have seen drastic improvements in their vision after undergoing gene therapy. The research began in 2008 at the University of Pennsylvania's Mahoney Institute of Neurological Sciences where Jean Bennett and her team tested their gene therapy on 12 individuals with LCA.

Each of the 12 people invovled in the study were treated in just one eye to start with, their eye with the worst vision. They were injected with a harmless virus that carried a normal copy of the mutated gene that causes LCA. Once the virus and normal gene were injected into the retinal pigment epithelium it began to produce an enzyme critical for healthy photoreceptors, an enzyme that people with LCA are lacking.

Of the 12 patients, six experienced such vast improvements in their vision that they no longer were considered legally blind.

More recent studies from the same group of Bennett's have involved treating the second eyes of three women from the original twelve. Within just two weeks after surgery the women noticed significant improvements in their vision.

Bennett explains that the brain seemed to respond in an even stronger way once the second eye was injected with the normal gene. She says "That wasn't something we had been expecting, but it makes sense because the two eyes act in concert, and some aspects of vision rely on binocularity."

Though this research included adults, Bennett suspects that future research is especially promising for younger patients who have not yet lost as many healthy photoreceptors.

To learn more about this revolutionary breakthrough contact an ophthalmologist near you.