Autosomal recessive 'optic atrophy' with late onset and evidence of ganglion cell dysfunction: a sibship of two females.

Two sisters aged about 40 years presented with a recent moderate reduction in visual acuity and pale optic discs. The nonconsanguineous parents, 7 other siblings and all other family members have normal vision. This strongly indicates a hereditary, autosomal recessive origin. A primary ganglion cell pathology is strongly suspected because of the significant attenuation of the early component of the onset/offset visual-evoked potential in the presence of little change in the potential to a pattern reversal stimulus.