To the best of our knowledge, this study represents the largest effort to determine the genetic alterations underlying BCD in Spain to date. Our results show that analysis of CYP4V2 variants is required for a reliable diagnosis of BCD. We report a high prevalence of anterior segment changes in this Spanish BCD cohort, which we consider representative of the Spanish patients.

The authors identified a case of Bietti crystalline dystrophy with central and paracentral keratopathy and the molecular analysis of the causative gene in a Spanish family. Data suggest a dose-dependent phenotype ranging from subclinical corneal changes in subjects carrying 1 mutant Ile111Thr CYP4V2 allele to the complete manifestation of the disease in homozygous subjects. In vivo corneal confocal microscopy is a useful technique in the diagnosis of this disorder.