Autosomal dominant cone-rod dystrophy associated with mutations in codon 244 (Asn244His) and codon 184 (Tyr184Ser) of the peripherin/RDS gene.
OBJECTIVE
To characterize clinical findings associated with mutations in codon 244 (Asn244His) and codon 184 (Tyr184Ser) of the peripherin/RDS gene.


METHODS
Case reports with clinical features and results of fluorescein angiography, electroretinography, kinetic visual field testing, and DNA analysis.


METHODS
University medical center.


METHODS
Four affected members of two Japanese families with autosomal dominant cone-rod dystrophy associated with transversion mutations in codon 244 (Asn244His) and codon (Tyr184Ser) of the peripherin/RDS gene.


RESULTS
Characteristic features included the initial symptoms of decreased visual acuity, macular degeneration, central or paracentral scotoma, cone-mediated electroretinographic responses that were more impaired than rod-mediated responses, and pigmentary degeneration in the midperipheral retina in the late stage. These phenotypic features corresponded to cone-rod dystrophy type 2a by the classification of Szlyk and associates.


CONCLUSIONS
The Asn244His and Tyr184Ser mutations in the peripherin/RDS gene cause con-rod dystrophy type 2a. These findings imply that a mutation in codon 244 or codon 184 of the peripherin/RDS gene affects the functions and/or structural stability of cones and rods.
Nakazawa
M
M
Department of Ophthalmology, Tohoku University School of Medicine, Sendai, Japan.
Kikawa
E
E
Chida
Y
Y
Wada
Y
Y
Shiono
T
T
Tamai
M
M
D000328:Adult; D000368:Aged; D000595:Amino Acid Sequence; D001216:Asparagine; D001483:Base Sequence; D003062:Codon / Q000235:genetics*; D004247:DNA / Q000032:analysis; D004596:Electroretinography; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D005451:Fluorescein Angiography; D006639:Histidine; D006801:Humans; D007381:Intermediate Filament Proteins / Q000235:genetics*; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics; D008875:Middle Aged; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins; D010375:Pedigree; D064531:Peripherins; D010786:Photoreceptor Cells / Q000473:pathology*; D017354:Point Mutation; D018807:Polymorphism, Single-Stranded Conformational; D012162:Retinal Degeneration / Q000235:genetics* / Q000473:pathology; D012694:Serine; D014443:Tyrosine; D014794:Visual Fields
D003062:Codon; D005136:Eye Proteins; D007381:Intermediate Filament Proteins; D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; C578994:PRPH protein, human; C578997:PRPH2 protein, human; D064531:Peripherins; D014443:Tyrosine; D012694:Serine; D006639:Histidine; D001216:Asparagine; D004247:DNA