GAINESVILLE, Fla. -- A University of Florida neuroscientist has discovered and cloned a mutant gene in chickens, helping researchers better understand a rare human eye disease that causes blindness at birth.
Sue Semple-Rowland, an associate professor of neuroscience in UF's College of Medicine and the UF Brain Institute, has established a specific type of the Rhode Island Red chicken as the animal model for studying the human disease, called Leber's congenital amaurosis type I, or LCA-I. She will present her work Thursday at the Eighth International Symposium on Retinal Degeneration in Schluchsee, Germany.
"The way the retina works is similar in chickens and humans, so I think it is reasonable to assume that what we develop in this lab for the chicken will be something that could be very useful in treating people," Rowland said.
Rowland now is developing a form of gene therapy for chickens with the disease.
"The eye offers a unique opportunity to employ gene therapy because it is a closed system," she said. "The cells in the eye are highly specialized for the work they do, which enables us to better target them for gene therapy."
LCA-I is among the earliest and most severe forms of autosomal recessive inherited retinal degeneration. Autosomal recessive diseases occur when a person receives a defective copy of a particular gene from both parents.
The retina, a light-sensitive tissue at the back of the eye, contains photoreceptors called rods and cones. The receptors convert light into electrical and chemical signals, which are then sent to visual centers in the brain through the optic nerve. In people with LCA-I and in the retinal-degeneration chicken, the defective guanylate cyclase gene fails to make a protein needed for this basic visual process.
Cones, the receptors that enable color vision, are essential for human
sight. Chicken eyes have a high percentage of cones, which makes them
Contact: Paul Ramey
University of Florida