Gene therapy of the human retina

Retinal gene therapy holds a promise in treating different forms of non-inherited and inherited blindness. In 2008, three independent research groups reported that patients with the rare genetic retinal disease Leber's congenital amaurosis had been successfully treated using gene therapy with adeno-associated virus (AAV). In all three studies, an AAV vector was used to deliver a functional copy of the RPE65 gene, which restored vision in children suffering from LCA. These results were widely seen as a success in the gene therapy field, and have generated excitement and momentum for AAV-mediated applications in retinal disease. In retinal gene therapy, the most widely used vectors for ocular gene delivery are based on adeno-associated virus. The great advantage in using adeno-associated virus for the gene therapy is that it poses minimal immune responses and mediates long-term transgene expression in a variety of retinal cell types. For example, tight junctions that form the blood-retina barrier, separate subretinal space from the blood supply, providing protection from microbes and decreasing most immune-mediated damages. There is still a lot of knowledge missing in regards of retina dystrophies. Detail characterization is needed in order to improve knowledge. To address this issue, creation of Registries is an attempt to grouped and characterize rare diseases. Registries help to localize, and measure all the phenotype of these conditions and therefore to provide easy follow-ups and provide a source of information to scientist community. Registry designs varies from region to region, however localization and characterization of the phenotype are the standard gold. Examples of Registries are: RetMxMap. A Mexican and Latin-American registry created since 2009. This registry was created by Dr Adda Lízbeth Villanueva Avilés. She is a clinical-scientist gene mapping inherited retina dystrophies in Mexico and other Latin countries. Preclinical studies in mouse models of Leber's congenital amaurosis (LCA) were published in 1996 and a study in dogs published in 2001.