Color-deficient cone mosaics associated with Xq28 opsin mutations: a stop codon versus gene deletions.
Our understanding of the etiology of red-green color vision defects is evolving. While missense mutations within the long- (L-) and middle-wavelength sensitive (M-) photopigments and gross rearrangements within the L/M-opsin gene array are commonly associated with red-green defects, recent work using adaptive optics retinal imaging has shown that different genotypes can have distinct consequences for the cone mosaic. Here we examined the cone mosaic in red-green color deficient individuals with multiple X-chromosome opsin genes that encode L opsin, as well as individuals with a single X-chromosome opsin gene that encodes L opsin and a single patient with a novel premature termination codon in his M-opsin gene and a normal L-opsin gene. We observed no difference in cone density between normal trichomats and multiple or single-gene deutans. In addition, we demonstrate different phenotypic effects of a nonsense mutation versus the previously described deleterious polymorphism, (LIAVA), both of which differ from multiple and single-gene deutans. Our results help refine the relationship between opsin genotype and cone photoreceptor mosaic phenotype.
Wagner-Schuman
Melissa
M
Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI 53226, United States.
Neitz
Jay
J
Rha
Jungtae
J
Williams
David R
DR
Neitz
Maureen
M
Carroll
Joseph
J
D000293:Adolescent; D000328:Adult; D002648:Child; D018388:Codon, Terminator; D003117:Color Vision Defects / Q000235:genetics* / Q000503:physiopathology*; D055358:Cone Opsins / Q000235:genetics*; D005260:Female; D017353:Gene Deletion; D050172:Genes, X-Linked / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D012160:Retina / Q000473:pathology; D017949:Retinal Cone Photoreceptor Cells / Q000473:pathology*; D017422:Sequence Analysis, DNA; D055815:Young Adult
D018388:Codon, Terminator; D055358:Cone Opsins