Evaluation of macular structure and function by OCT and electrophysiology in patients with vitelliform macular dystrophy due to mutations in BEST1.
OBJECTIVE
To analyze retinal structure and function in vitelliform macular dystrophy (VMD) due to mutations in BEST1.


METHODS
Patients from five Swedish and four Danish families were examined with electrooculography (EOG), full-field electroretinography (ffERG), multifocal ERG (mfERG), optical coherence tomography (OCT), and fundus autofluorescence photography (FAF). Genetic analysis of the BEST1 gene was performed by direct sequencing.


RESULTS
Mutations in BEST1 have been reported previously in the Swedish families. In the Danish families, four disease-causing missense mutations were found, one of which is novel: c.936C>A (p.Asp312Glu). The mutation was homozygous in a 9-year-old boy and heterozygous in his father in a consanguineous family. ffERG rod response was reduced in the homozygous boy, but normal in the heterozygous father. EOG was reduced in all but two patients and did not correlate with the ffERG results. OCT ranged from normal to cystoid edema and thickening of the outer retina-choroid complex. Decreased mfERG amplitudes, increased mfERG latencies, and loss of integrity of the foveal photoreceptor inner/outer segment junction, correlated with decreased vision. FAF demonstrated hyperautofluorescence beyond the ophthalmoscopic changes in several patients.


CONCLUSIONS
The finding of a homozygous dominant mutation in a patient with VMD and evidence of widespread retinal degeneration may imply that the pathogenesis of the generalized retinal degeneration differs from that of the macular degeneration. A relative agreement between hyperautofluorescence by FAF, reduced retinal function, and VMD implies that the hyperautofluorescence emanates from lipofuscin and A2E. A potential therapy for VMD, involving the inhibition of the retinoid cycle, is suggested.
Schatz
Patrik
P
Department of Ophthalmology, Glostrup Hospital, University of Copenhagen, Glostrup, Denmark. patrik.schatz@med.lu.se
Bitner
Hanna
H
Sander
Birgit
B
Holfort
Stig
S
Andreasson
Sten
S
Larsen
Michael
M
Sharon
Dror
D
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D000075002:Bestrophins; D002648:Child; D018118:Chloride Channels / Q000235:genetics*; D004585:Electrooculography; D005136:Eye Proteins / Q000235:genetics*; D005192:Family Health; D005260:Female; D005453:Fluorescence; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D008266:Macula Lutea / Q000473:pathology*; D008268:Macular Degeneration / Q000235:genetics* / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D010375:Pedigree; D041623:Tomography, Optical Coherence; D055815:Young Adult
C113133:BEST1 protein, human; D000075002:Bestrophins; D018118:Chloride Channels; D005136:Eye Proteins