Two studies published online on April 27, 2008, in The New England Journal of Medicine report results of gene therapy treatment for Leber congenital amaurosis (LCA), an inherited retinal degenerative disorder that causes an infant to be born with severely impaired vision. Two separate research teams each treated three individuals with LCA. One study showed no change in patients' visual acuity, but all three patients in the other study found a gain in visual acuity. The ability to see things, however, is based on a person's perception, so it is possible that any improved vision was not due to the gene therapy. An accompanying editorial in the medical journal also states that measuring visual acuity in people with very low vision (like those in the two studies) is not reliable.

What it all means: the results indicate the gene therapy procedure is safe, and it might have some benefits, but larger groups of people with LCA need to be studied for longer periods of time to get better information about this possible treatment.

Bainbridge, James et al. "Effect of Gene Therapy on Visual Function in Leber's Congenital Amaurosis." The New England Journal of Medicine (2008): ePub.

Maguire, Albert et al. "Safety and Efficacy of Gene Transfer for Leber's Congenital Amaurosis." The New England Journal of Medicine (2008): ePub.