Purchase this article with an account.
Settimio Rossi, Francesco Testa, Michele Della Corte, Anren Li, Valentina Di Iorio, Carlo Gesualdo, J. Fielding Hejtmancik, Francesca Simonelli; Characterization of Italian Bietti Crystalline Dystrophy Patients with CYP4V2 Mutations. Invest. Ophthalmol. Vis. Sci. 2011;52(14):1833.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
The aim of this study was to investigate the spectrum of mutations in CYP4V2 gene in Italian Bietti Crystalline Dystrophy (BCD) patients, and to correlate the patients' mutations with their phenotypes.
15 patients in 10 families with BCD were recruited for full ophthalmic examinations, optical coherence tomography (OCT), and full-field electroretinography (ERG). Peripheral venous blood was obtained from all index patients and their family members for genomic DNA extraction and CYP4V2 direct sequence screening.
Nine pathogenic mutations in all 15 patients were identified in the CYP4V2 gene. Patients (mean age of 49 ± 7.3 years) had mean visual acuity of 0.6 ± 0.5. Slit-lamp examination showed no limbal crystals In the cornea. Dilated fundus examination showed the presence of intraretinal crystalline deposits in the posterior pole of all 15 patients. Other retinal findings included bone spicule pigmentation, retinal vascular attenuation and diffuse choriocapillaris atrophy. There was some variation in the clinical phenotypes and in the amount of crystalline deposits among the patients. Even in patients with the same genotype, the clinical phenotypes may be rather different. OCT showed the presence of intraretinal crystals and thinning of the retina at the central macular region in all patients. Analysis of the ERG recordings showed that 5 of the 15 patients (33%) had nonrecordable ERGs, whereas only 2 (13%) had normal ERGs and the remaining 8 patients (54%) have subnormal scotopic and photopic responses.
This study identified nine mutations in the CYP4V2 gene as a cause of BCD in Italian patients. Phenotype characterization showed clinical heterogeneity and suggests the existence of less severe forms of BCD characterised by classical retinal lesions with a normal electroretinogram.
This PDF is available to Subscribers Only