Clinical and molecular findings in three Japanese patients with crystalline retinopathy.
OBJECTIVE
To identify CYP4V2 mutations in three unrelated Japanese patients with Bietti crystalline corneoretinal dystrophy (BCD).


METHODS
The three cases were diagnosed by ophthalmological examinations. All exons and flanking introns were amplified by polymerase chain reaction (PCR). PCR products were analyzed by direct sequencing. RNA was extracted from blood samples and analyzed by reverse transcriptase (RT)-PCR sequencing.


RESULTS
Direct PCR sequencing demonstrated a homozygous mutation involving a 17-bp deletion together with a 2-bp insertion (c.802-8del17bp/insGC) in case 1 and case 3, and RT-PCR demonstrated that the complete length of exon 7 was missing; case 2 showed only a heterozygous change in exon 11 with no second mutation.


CONCLUSIONS
A homozygous mutation was identified in two of the unrelated patients, and only a heterozygous change was detected in the third. These data indicate that c.802-8del17bp/insGC may be a frequent mutation in this gene.
Jin
Zi-Bing
ZB
Department of Ophthalmology and Visual Science, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.
Ito
Shigeo
S
Department of Ophthalmology, National Hospital Organization, Osaka National Hospital, Osaka, Japan.
Saito
Yoshihiro
Y
Department of Ophthalmology, National Hospital Organization, Osaka National Hospital, Osaka, Japan.
Inoue
Yuji
Y
Department of Ophthalmology, University of Tokyo School of Medicine, Tokyo, Japan.
Yanagi
Yasuo
Y
Department of Ophthalmology, University of Tokyo School of Medicine, Tokyo, Japan.
Nao-I
Nobuhisa
N
Department of Ophthalmology and Visual Science, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan. naoi@fc.miyazaki-u.ac.jp.
D000368:Aged; D003317:Corneal Dystrophies, Hereditary / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D003459:Crystallins / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D000072470:Cytochrome P450 Family 4; D003937:Diagnosis, Differential; D005091:Exons; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009154:Mutation; D012313:RNA / Q000235:genetics*; D012162:Retinal Degeneration / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D003459:Crystallins; D012313:RNA; D003577:Cytochrome P-450 Enzyme System; C505357:CYP4V2 protein, human; D000072470:Cytochrome P450 Family 4