[Progress in somatic gene therapy of retinal degeneration in the animal model]

More than 60 genes responsible for human retinal dystrophies have already been identified. Most of them are either expressed in the photoreceptor or in the retinal pigment epithelium (RPE). Therefore these cells have become the target of new therapeutical strategies on a molecular level. The most promising approach at present is somatic gene therapy, which has been developed over the last years and the principle has now been established in animal models. For gene therapy of inherited retinal degeneration, as for gene therapy in general, gene transfer has to be proven to be not only efficient but also safe. This has recently been achieved using the adeno-associated virus (AAV) as a vector to express a therapeutic gene within the photoreceptor cell. It could be demonstrated in mouse and dog models of retinal degeneration that expression of the therapeutic transgene leads to anatomical and functional restitution of degenerating photoreceptors. A significant immune response to AAV has not been detected so far. In this paper the recent success of gene therapy of retinal degeneration in animal models is reviewed.