Psychophysical and electrophysiological techniques are used to evaluate a family with progressive cone degeneration. Affected patients have monophasic dark-adaptation curves with normal rod thresholds, absent color vision, and reduction or absence of the cone components with normal rod components in the electroretinogram (ERG). Scotopic luminosity curves and ERGs with scotopically balanced lights suggest that their rhodopsin has a normal absorption spectrum. The defect in the cone system does not appear to influence dark adaptation of the rod system. This report confirms the dominant genetic pattern of this disease.
Berson EL, Gouras P, Gunkel RD. Progressive Cone Degeneration, Dominantly Inherited. Arch Ophthalmol. 1968;80(1):77-83. doi:10.1001/archopht.1968.00980050079011