Several phenotype-specific disorders of the eye – the retina being a distant yet integral outpost of the central nervous system – may also prove appropriate targets for cell therapy. Loss of the retinal pigment epithelium (RPE) in macular degeneration has been a particular target of interest, in that efficient protocols for generating RPE cells from both hESC and iPSCs have been developed. On that basis, hESC- and hiPSC-derived RPEs are both now in early safety trials for macular degeneration (Kamao et al., 2014; Nazari et al., 2015; Schwartz et al., 2015; Song et al., 2015; Whiting et al., 2015). More broadly, macular degeneration may be the first of a number of retinal disorders to be targeted for cell therapy; as more efficient protocols are developed for producing specific retinal phenotypes from hES and hiPS cells, a broad variety of both intrinsic retinal disorders and optic neuropathies may prove appropriate targets for phenotype-specific cell replacement. In particular, both rod and cone photoreceptors, lost in disorders as varied as macular degeneration, retinitis pigmentosa and glaucoma, among other etiologies, appear potentially replaceable by
