Chondroitin sulfate proteoglycan-5 (CSPG5) is a transmembrane protein that is abundantly expressed on the surface of nerve and glial cells, primarily required for the formation of the central nervous system; however, CSPG5 mRNA and protein expression were discovered in the retina and retinal pigment epithelium in the Leber congenital amaurosis model [12,13,14,15,16]. This evidence concerns the gene CSPG5 and Leber congenital amaurosis.