Monday, December 5, 2011
Seeing is Believing: Gene Therapy Shows Promise for Ocular Disorders
This article explains new technologies for the treatment of Leber Congenital Amaurosis (LCA), a group of degenerative diseases of the retina which are typically inherited through the autosomal recessive pattern. LCA is the most common cause of congenital blindness in children, but these new gene therapy treatments have proven promising.
In the early 1990’s, scientists found many mutations which cause blinding diseases including one in RPE65 which causes Type 2 Leber Congenital Amaurosis (LCA2). Researchers at the University of Pennsylvania also found it possible to transfer healthy genes into retinal cells using viruses. Because retinal cells are terminally differentiated at birth, this treatment method is especially convenient and in the retina.
While the results of the treatment are most dramatic in children, the visual function of all treated patients has improved. All patients have in fact requested bilateral treatment following treatment in one eye. Ideally, treatment should be delivered between 3 months and 6 years of age. The treatment has also been used to give color-blind squirrel monkeys color vision. The frontier for retinal gene therapy therefore is multifaceted and promising in many ways.