Ocular findings associated with a rhodopsin gene codon 58 transversion mutation in autosomal dominant retinitis pigmentosa
G. A. Fishman, E. M. Stone, L. D. Gilbert, P. Kenna and V. C. Sheffield
Department of Ophthalmology, University of Illinois, Chicago 60612.
Eight members of a family with autosomal dominant retinitis pigmentosa were
found to have a cytosine-to-guanine (C-to-G) transversion mutation in the
second nucleotide of codon 58 of the rhodopsin gene, causing a substitution
of the amino acid arginine for threonine. Five of these individuals were
examined clinically. There was a distinct phenotypic expression of the gene
defect within this family that included a regional predilection for
pigmentary changes in the inferior and inferonasal parts of the retina, as
well as field impairment predominantly in the superior hemisphere.
Characteristic electroretinographic recordings and psychophysical threshold
profiles also helped to identify this phenotype that, on a relative basis,
causes less severe photoreceptor cell functional impairment than often
occurs in other subtypes of retinitis pigmentosa. This report documents the
association of a clinically recognizable phenotype in a family with
autosomal dominant retinitis pigmentosa and a specific gene defect at the
molecular level.
