Screening for mutations in CYP4V2 gene in Japanese patients with Bietti's crystalline corneoretinal dystrophy

Am J Ophthalmol. 2005 May;139(5):894-9. doi: 10.1016/j.ajo.2004.11.065.


Purpose: To describe the clinical and genetic characteristics of six Japanese families with Bietti's crystalline corneoretinal dystrophy (BCD).

Design: Case reports and results of DNA analysis.

Methods: Mutation screening was performed on six unrelated patients with BCD by direct sequencing. The clinical features were characterized by the visual acuity, slit-lamp biomicroscopy, electroretinography, fluorescein angiography, and kinetic visual field testing.

Results: An identical IVS6 to 8delTCATACAGGTCATCGCG/insGC mutation in the CYP4V2 gene was identified in five of the patients with BCD; the sixth patient had a novel Trp340X mutation in the CYP4V2 gene. Three patients showed crystalline-like deposits at the limbus by specular microscopy. Ophthalmic findings of all patients had a rapid progression after age 50 years.

Conclusions: Our findings suggest that the IVS6 to 8delTCATACAGGTCATCGCG/insGC mutation is a common mutation in Japanese patients with BCD. Although phenotypic variability was found, the natural course was almost the same in all of our patients.

MeSH terms

  • Adult
  • Asian People
  • Chromosomes, Human, Pair 4 / genetics
  • Corneal Dystrophies, Hereditary / ethnology
  • Corneal Dystrophies, Hereditary / genetics*
  • Cytochrome P-450 Enzyme System / genetics*
  • DNA Mutational Analysis
  • Electroretinography
  • Female
  • Fluorescein Angiography
  • Genetic Linkage
  • Genetic Testing*
  • Humans
  • Male
  • Middle Aged
  • Mutation*
  • Pedigree
  • Polymerase Chain Reaction
  • Retinal Degeneration / ethnology
  • Retinal Degeneration / genetics*
  • Visual Acuity
  • Visual Fields


  • Cytochrome P-450 Enzyme System