The familial occurrence of retinal dysplasia in five affected male children suggested X-chromosome-linked recessive inheritance. The clinical features were childhood onset, severe visual impairment, head posture, nystagmus, and strabismus. The ophthalmoscopic findings varied in shape and extension; they ranged from retinal folds to dysplastic tissue covering the posterior pole or gliosis with tumor-like protrusion in the vitreous. The marked variability of the retinal findings was paralleled by the visual acuity, which ranged from some vision to blindness. Electroretinograms coordinated well with ophthalmoscopic observations. Of the five mothers, who are the presumed heterozygous carriers, two showed retinal changes.