A novel Gly35Ser mutation in the RDH5 gene in a Japanese family with fundus albipunctatus associated with cone dystrophy.
OBJECTIVE
To assess the clinical and genetic characteristics of a Japanese family with fundus albipunctatus with progressive cone dystrophy associated with a mutation in the RDH5 gene.


METHODS
Case report with clinical findings and results of fluorescein angiography, electroretinograms, kinetic visual field testing, dark adaptometry, and DNA analysis.


METHODS
University medical center.


METHODS
We studied the ocular findings in 6 members of a Japanese family with fundus albipunctatus with cone dystrophy and a guanine-to-adenine transversion at the first nucleotide in codon 35 of the RDH5 gene. The mutation resulted in a substitution of serine for glycine in amino acid 35 (Gly35Ser) of the RDH5 gene.


RESULTS
Characteristic features included poor night vision, white dots in the retina, cone dystrophy, and a mottled appearance of the retinal pigment epithelium. Electroretinograms showed greater impairment of the rod-mediated responses than the cone-mediated responses. After 3 hours of dark adaptation, the a and b waves and scotopic b waves recovered.


CONCLUSIONS
Although the mutation of the RDH5 gene has been known as a causative gene of fundus albipunctatus, the Gly35Ser mutation in the RDH5 gene may be related to the pathogenesis of progressive retinal degeneration. This phenomenon may provide evidence of gene phenotype caused by a mutation in the RDH5 gene.


CONCLUSIONS
The Gly35Ser mutation causes fundus albipunctatus with cone dystrophy. This finding provides evidence that some kinds of mutations in the RDH5 gene are related, in part at least, to the pathogenesis of progressive retinal degeneration.
Wada
Y
Y
Department of Ophthalmology, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-77, Japan. yukow@oph.med.tohoku.ac.jp
Abe
T
T
Sato
H
H
Tamai
M
M
D000429:Alcohol Oxidoreductases / Q000235:genetics*; D004252:DNA Mutational Analysis; D003623:Dark Adaptation; D004596:Electroretinography; D005451:Fluorescein Angiography; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009755:Night Blindness / Q000201:enzymology / Q000208:ethnology / Q000235:genetics* / Q000503:physiopathology; D010375:Pedigree; D017354:Point Mutation; D017949:Retinal Cone Photoreceptor Cells / Q000201:enzymology / Q000503:physiopathology*; D012162:Retinal Degeneration / Q000201:enzymology / Q000208:ethnology / Q000235:genetics* / Q000503:physiopathology; D017948:Retinal Rod Photoreceptor Cells / Q000201:enzymology / Q000503:physiopathology; D014794:Visual Fields / Q000502:physiology
D000429:Alcohol Oxidoreductases; C022520:retinol dehydrogenase