While a number of retinal transplantation studies using various types of donor cells have been performed thus far, our study focused on iris tissue as a donor cell source. This is because donor cells from iris pigment epithelium have the following characteristics: (1) they are embryonically related to the neural retina; (2) autologous iris tissue can be obtained via a surgical approach; and (3) they can be cultured to increase the number of donor cells and establish photoreceptor-like cells from iris-derived cells by means of the appropriate gene transfer. Although the potential of iris-derived cells has been indicated, there remain many issues to be investigated.