13 months ago, Corey Haas couldn't have seen his way to walk up steps.
He was born with LCA, a genetic disease that causes light-receptor cells in the back of the eye to deteriorate.
His field of vision had become so narrow he could only see parts of objects.
Corey couldn't navigate a small obstacle course without bumping into things.
Last September, doctors from the Children's Hospital and the University of Pennsylvania injected a corrected copy of the gene that is defective into the back of Corey's eye.
Not long afterward, Nancy Haas noticed her son could see and pick up things he dropped.
"He wouldn't have been able to do that before," Corey's mother Nancy said as she began crying.
Three months after the injection, Corey had no trouble with the obstacle course.
"He immediately follows the course, he's following all the turns, not making any mistakes," Dr. Jean Bennett said.
The Penn researchers have had success before in using the gene therapy with a handful of adults, but this portion of the clinical trials, with Corey and four other children, was especially rewarding.
"I think we'll be hearing more about good results with gene therapy," Dr. Katherine High of children's Hospital said.
In fact, the research team hopes to begin a new phase in January, aimed at getting FDA approval for their treatment. They think it also has the potential to fix many other eye diseases in the future.
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