Ocular findings associated with rhodopsin gene codon 17 and codon 182 transition mutations in dominant retinitis pigmentosa
G. A. Fishman, E. M. Stone, V. C. Sheffield, L. D. Gilbert and A. E. Kimura
Department of Ophthalmology, University of Illinois, Chicago 60612.
Six members of a family with autosomal dominant retinitis pigmentosa were
found to have a cytosine-to-thymine transition mutation in the second
nucleotide of codon 17 in the rhodopsin gene that resulted in a threonine
to methionine change. Three members from another family with autosomal
dominant retinitis pigmentosa showed a guanine-to-adenine transition
mutation in the first nucleotide of codon 182 in the rhodopsin gene that
resulted in a glycine to serine change. Each of these two mutations
presented with a similar phenotype because both showed a regional
predilection for pigmentary changes to occur in the inferior part of the
retina as well as field impairment predominantly in the superior
hemisphere. Electroretinographic amplitudes were more substantial than
usually encountered in other forms of retinitis pigmentosa, a finding
consistent with the better visual prognosis in patients with either of
these two mutations. This article documents the association of two similar
phenotypes of autosomal dominant retinitis pigmentosa with specific gene
defects at a molecular level.
