Abstract
Abstract: :
Purpose: To compare histologic findings in autopsy eyes from a 63-year-old patient with a dominant mutation in the RP13 gene (PRPC8, Arg2310Gly) with those of a 77-year-old patient with rhodopsin Pro23His, a 76-year-old patient with Cys110Arg, and an 88-year-old patient with Glu181Lys. The eyes of the patient with PRPC8 have been previously described when no mutation was known, (Szamier and Berson, IOVS 16:947,1977). The PRPC8 mutation is thought to affect pre-mRNA splicing, while the rhodopsin defects are thought to affect the folding and stabilization of opsin. Methods: All eyes were fixed between 1-12 hours after death in a phosphate buffer containing 2.5% glutaraldehyde and 1% formaldehyde. Results: The patient with the PRPC8 mutation had no rod photoreceptors and a reduced number of cone photoreceptors with shortened or absent outer segments. The cones contained perinuclear membranous swirls and inclusion bodies in the inner segments. The RPE and choroid were intact. The patients with rhodopsin mutations also showed no rod photoreceptors; the remaining cones had shortened or absent outer segments and inner segments apposed to the RPE. The cone photoreceptors in the Cys110Arg and Glu181Lys retinas had inclusion bodies; the latter had also membranous swirls. Patients with Pro23His and Glu181Lys showed only patches of RPE and underlying choroid, while the patient with Cys110Arg had intact RPE and choroid. Conclusions: In these patients with advanced RP, we could find no distinctive feature that distinguishes the pathology caused by mutations in the PRPC8 gene versus mutations in the rhodopsin gene. Shared findings include absent rod photoreceptors; the remaining cones have shortened or absent outer segments, perinuclear membranous swirls, and inclusion bodies. Support: The Foundation Fighting Blindness
Keywords: 562 retinal degenerations: hereditary • 507 pathology: human • 472 microscopy: electron microscopy