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(Best Syndication News) University of Florida researchers report that gene therapy can improve the vision in adult humans who were born with “extremely impaired sight”. The brain actually rewires itself to recognize sections of the retina that were treated with this technique.

One patient was able to see the digital clock in the car using her treated eye. She was never able to read the time with either eye. So far three volunteers have received doses of corrective genes in selected areas of their retinas at Shands at the University of Florida medical center.

The scientists decided to compare various regions of the retina to see where they focusing. They measured where her gaze was fixed while looking at a variety of dim targets. Amazingly, the participants had two preferred centers of vision rather than one. The region of the retina depended on the brightness of the object.

Although the new region is more sensitive to light, it is not as precise as the fovea for making bright images sharp. The fovea, located in the center of the macula region of the retina, is responsible for sharp central vision. We use it for reading, watching TV and driving. The fovea has the highest density of rods. These rod cells are sensitive enough to respond to one single photon of light and are responsible for night vision.

William W. Hauswirth, Ph.D., says that the patient automatically uses that portion of the eye that is most appropriate for seeing any object. "Her brain tells her to use the best part of retina she can, depending on the situation, so she automatically shifts back and forth between the usual region and the region we supplied to her." Hauswirth is a professor in the ophthalmology department at the UF College of Medicine.

Even more amazing than the repair to the eye, is how well the brain is adapting to those changes. The brain is adapting to the changes in the treated eye, says aid John G. Flannery, Ph.D., a professor of vision science, and neurobiology at the Helen Wills Neuroscience Institute at the University of California, Berkeley. "You could almost say the patients' brains are getting better at paying attention to the gene-therapy treated area, because it is functioning at a higher level."

By Marsha Quinn
Health Writer