A novel ABCR nonsense mutation responsible for late-onset fundus flavimaculatus

PURPOSE. TO report the ophthalmologic features of a novel truncating mutati on in the ABCR gene in a patient affected with late-onset fundus flavimacul atus (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 indocy anine green angiographies, visual field testing, color vision analysis, ele ctroretinogram, and electro-oculogram. The 50 exons of the ABCR gene were a nalyzed using direct sequencing. RESULTS. Fluorescein and indocyanine green angiographies confirmed the diag nosis of FFM. A heterozygous base change was found, resulting in the substi tution of an arginine to a stop at codon 152 of the ABCR gene. CONCLUSIONS. A heterozygous nonsense ABCR gene mutation was found in a pati ent affected with FFM. NO other mutation has been identified in the entire coding sequence and the promoter region, suggesting that a heterozygous sev ere ABCR mutant may be responsible for a mild and delayed FFM phenotype? di fferent from that of age-related macular degeneration.