Inherited retinal degenerative diseases such as retinitis pigmentosa (RP), Leber Congenital Amaurosis (LCA), Batten Disease, Usher Syndrome, BBS and Best disease are collectively a major cause of incurable blindness in the western world. Although a myriad of different genes/mutations are responsible for causing these diseases, each are characterized by death of the light sensing photoreceptor cells of the outer neural retina.

Two major therapeutic approaches under development in my laboratory for the treatment of this class of disease are:
1: Gene replacement therapy
2: Cell replacement therapy

The determination as to which of these two treatment strategies are selected is dependent upon both knowledge of disease gene/mechanism and disease course/progression.

For patients with an inherited retinal degenerative disease with identified disease causing gene/mutations an attractive strategy would be to replace the defective gene, preferably early in disease course, in an attempt to prevent photoreceptor cell death.

For patients with no known disease causing gene the ability to intervene using a gene replacement strategy prior to photoreceptor cell death and subsequent loss of vision is limited. As the intrinsic regenerative capacity of the mammalian retina is extremely limited, for these people an autologous patient specific induced pluripotent stem cell (iPSCs) based photoreceptor cell replacement approach is being developed.

For many patients a combination of these two approaches will undoubtedly be useful.