A novel ABCR nonsense mutation responsible for late-onset fundus flavimaculatus.
OBJECTIVE
To report the ophthalmologic features of a novel truncating mutation in the ABCR gene in a patient affected with late-onset fundus flavimaculatus (FFM).


METHODS
A complete ophthalmologic examination was performed in a 70-year-old patient, including best-corrected visual acuity measurement, slit lamp and fundus examination, fundus photographs, frequent fluorescein and indocyanine green angiographies, visual field testing, color vision analysis, electroretinogram, and electro-oculogram. The 50 exons of the ABCR gene were analyzed using direct sequencing.


RESULTS
Fluorescein and indocyanine green angiographies confirmed the diagnosis of FFM. A heterozygous base change was found, resulting in the substitution of an arginine to a stop at codon 152 of the ABCR gene.


CONCLUSIONS
A heterozygous nonsense ABCR gene mutation was found in a patient affected with FFM. No other mutation has been identified in the entire coding sequence and the promoter region, suggesting that a heterozygous severe ABCR mutant may be responsible for a mild and delayed FFM phenotype, different from that of age-related macular degeneration.
Souied
E H
EH
Institut National de la Santé et de la Recherche Médicale U-393, Hôpital des Enfants-Malades, Paris, France.
Ducroq
D
D
Rozet
J M
JM
Gerber
S
S
Perrault
I
I
Sterkers
M
M
Benhamou
N
N
Munnich
A
A
Coscas
G
G
Soubrane
G
G
Kaplan
J
J
D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D017668:Age of Onset; D000368:Aged; D018388:Codon, Terminator / Q000235:genetics; D004252:DNA Mutational Analysis; D017931:DNA Primers / Q000737:chemistry; D005451:Fluorescein Angiography; D005654:Fundus Oculi; D006801:Humans; D007208:Indocyanine Green; D008268:Macular Degeneration / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D009154:Mutation; D018807:Polymorphism, Single-Stranded Conformational; D012374:Rod Cell Outer Segment / Q000473:pathology*
C056475:ABCA4 protein, human; D018528:ATP-Binding Cassette Transporters; D018388:Codon, Terminator; D017931:DNA Primers; D007208:Indocyanine Green