Deletion in the peripherin/RDS gene in two unrelated Sardinian families with autosomal dominant butterfly-shaped macular dystrophy.
BACKGROUND
Autosomal dominant butterfly-shaped macular dystrophy is associated with different mutations of the peripherin/RDS gene. We studied the phenotype of two families with a novel large deletion in the peripherin/RDS gene.


METHODS
Clinical study, fluorescein angiography, color vision testing, automatic perimetry, electrophysiologic studies, and DNA analysis were performed on all the members of the two families.


RESULTS
Fundus examination in patients aged 30 to 60 years showed yellow deposits in the macula with a butterfly-shaped pattern. Central choroidal atrophy was present in the older patients only. Macular visual function tests (color vision and central visual field) were abnormal, and electro-oculograms were slightly subnormal in five individuals tested. Electroretinograms and results of dark adaptometry were normal. Linkage analysis with intragenic polymorphic markers and quantitative polymerase chain reaction showed heterozygosity for a large deletion that removed exons 2 and 3 of the peripherin/RDS gene in all affected members of two families.


CONCLUSIONS
This deletion escaped detection by direct analysis of amplified exons and was identified by intragenic polymorphic markers analysis, resulting in loss of heterozygosity from affected parents to affected children, and by quantitative polymerase chain reaction. The delineation of the molecular defect associated with the disease in these two families allows us to verify the presence or absence of the disease in clinically unaffected members.
Fossarello
M
M
Institution of Clinical Ophthalmology, University of Cagliari (Italy).
Bertini
C
C
Galantuomo
M S
MS
Cao
A
A
Serra
A
A
Pirastu
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D003118:Color Perception / Q000502:physiology; D004247:DNA / Q000032:analysis; D017931:DNA Primers; D004594:Electrophysiology; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D005451:Fluorescein Angiography; D005654:Fundus Oculi; D017353:Gene Deletion; D008040:Genetic Linkage; D006801:Humans; D007381:Intermediate Filament Proteins / Q000235:genetics*; D007558:Italy; D008268:Macular Degeneration / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics; D008875:Middle Aged; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins; D010375:Pedigree; D064531:Peripherins; D016133:Polymerase Chain Reaction; D058609:Visual Field Tests; D014794:Visual Fields / Q000502:physiology
D017931:DNA Primers; D005136:Eye Proteins; D007381:Intermediate Filament Proteins; D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; C578994:PRPH protein, human; C578997:PRPH2 protein, human; D064531:Peripherins; D004247:DNA