Recent developments in ocular gene therapy.

The past two to three years have witnessed a remarkable increase in the number of gene therapy studies to treat almost every disease of the eye. All types of delivery systems, viral and non-viral, have been used. Experiments have begun to move from the use of reporters, to genes with potential therapeutic value. In this paper, rather than giving an overview from the beginning of ocular gene therapy, I have chosen to review its most recent advances. Although numerous issues remain to be solved, the emerging picture is encouraging. Within the experimental setting, conditions in the anterior and posterior segments have been improved by the administration of genes encoding beneficial proteins. In one case, vision has been restored in a congenitally blind animal. Limitations do exit, however a greater understanding of the molecular biology of eye tissues coupled with the development of low immunogenicity vectors will continue edging the way for a future use of gene therapy in the clinical setting.