Phenotypes of Carboxyl-Terminal Rhodopsin Mutations in Autosomal Dominant Retinitis Pigmentosa
We compared the ocular findings in 13 patients from 4 families with autosomal dominant retinitis pigmentosa and 4 different mutations in the carboxyl-terminal sequence of rhodopsin. Phenotypic similarities were found among patients with point mutations predicting the amino acid changes valine-345-methionine, proline-347-serine or proline-347-leucine in the rhodopin molecule. These patients had no measurable rod function and an early impairment of cone function, which was most profound in the proline-347-serine genotype. One patient with a valine-345-methionine mutation showed a regional predilection of fundus abnormalities and cone sensitivity loss. A different phenotype with relatively mild disease expression could be observed in a family with a deletion of 8 base pairs (codons 341–343). One 34 year-old member showed regionally varying rod sensitivity loss, which was less severe in the peripheral visual field, and well maintained cone function, as measured by electroretinography and psychophysical tests.
KeywordsCodon Carboxyl Retina Serine Proline
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