Leber Congenital Amaurosis
Leber Congenital Amaurosis (LCA) is a severe retinal disease that affects children beginning in infancy. Some children with LCA are blind, while others have userful but extremely reduced central vision. other visual symptoms include nystagmus and photophobia (light sensitivity). Many children with LCA, especially those who are blind, will poke, press, and rub their eyes, which eventually leads to a "sunken" appearance of the eyes.
The definitive test for the diagnosis of LCA is the electroretinogram (ERG), which measures the electrical impulses generated by the rod and cone cells of the retina. in young children, the ERG is typically performed under sedation.
LCA is usually inherited as an autosomal recessive trait and affects males and females equally. In these cases, the parents of a child with LCA are both carriers and have a 1 in 4 chance of having an affected child with any pregnancy. Most children born with LCA have no affected family members.
Gene Clinics (Excellent medical genetics information web site)