Latest Update: Childhood Rediscovered: Gene Therapy Restores Vision for 9-year old with LCA

Researchers around the world are calling it a scientific breakthrough; a medical milestone. Corey’s parents, Ethan and Nancy, call it a dream come true.


Ethan, Nancy and Corey Haas
attend a press conference at
The Children’s Hospital of Philadelphia

Just 13 months ago Corey was almost completely blind. With poor visual acuity, little color perception and a very limited visual field, he was challenged in the most basic of childhood activities. Dependent on a white cane to simply make his way across a room, Corey was unable to play baseball or ride his bike around the neighborhood. He sat in the back of the classroom and relied on a teaching assistant and electronic screen to follow lessons in class. He had trouble seeing the faces of his own parents.

Now, after a single injection of genes that deliver light-sensitive pigment to the back of his eye, Corey has discovered a new world. At nine years old, he is the youngest of 12 individuals taking part in the groundbreaking study at CHOP, using gene therapy to treat Leber congenital amaurosis (LCA), a retinal disease that causes blindness or substantial vision loss at birth.

LCA is a very rare condition that affects only about 3,000 to 3,700 Americans. It is caused by a defect in one of 13 or 14 different genes. In Corey’s case, the defect is in the gene RPE65; defects in this gene account for 4 to 6 percent of all LCA cases. Dr. Bennett and a team of researchers at CHOP and the University of Pennsylvania School of Medicine have developed a way to deliver a healthy copy of that gene to the eye and, essentially, reverse the effects of the disease.

Corey was treated with gene therapy 13 months ago. Within just one month of treatment, he and his parents noticed major improvements in his vision. His eyes were responding to light and he was seeing colors more vividly. “One of his friends came over and Corey asked me when she had dyed her hair. Her hair color hadn’t changed. That’s when I knew that he was really starting to see colors,” recalls Ethan.
At his three-month review at CHOP, Corey was able to perfectly complete an obstacle course that, before treatment, he had trouble even attempting. Today, while his vision is not perfect, his acuity is vastly improved and his visual field is that of someone with normal vision. For the first time in his life, Corey is able to read large-print books and participate in class from the front row, with no help from visual aids.

Corey is now enjoying the freedom - and the childhood - that his new-found vision has afforded him. His favorite sports are baseball and soccer and he loves riding his bike around the neighborhood with friends. A year ago, Corey always had to be home by dusk, because LCA made it impossible for him to see in the dark. Now his parents have to go outside looking for him when dinner is ready.

Halloween is just around the corner and, with his restored vision, trick-or-treating this year should be a whole new experience. Thanks to gene therapy, Corey can now focus on the normal decisions of childhood. When asked what he’s going to be this year for Halloween, Corey smiles shyly. “I haven’t decided yet.”