Inherited retinal dystrophy: primary defect in pigment epithelium determined with experimental rat chimeras.

Chimeric rats were produced by the aggregation of embryos of the pinkeyed, retinal dystrophic RCS strain with those of pigmented, normal rats. In the mosaic eyes, patches of neural retina with abnormal and degenerated photoreceptors were present only opposite patches of nonpigmented, mutant pigment epithelium. This indicates that the retinal dystrophy gene acts in the pigment epithelial cell rather than in the photoreceptor cell.