Corneal Dystrophy, Fuchs Endothelial, 5

Description

Fuchs endothelial corneal dystrophy (FECD) is the most common genetic disorder of the corneal endothelium. Late-onset FECD is marked by thickening of Descemets membrane and excrescences, called guttae, that typically appear in the fourth or fifth decade. Disease progression results in decreased visual acuity as a result of increasing corneal edema, and end-stage disease is marked by painful epithelial bullae (summary by Riazuddin et al., 2013).

For a discussion of genetic heterogeneity of Fuchs corneal dystrophy, see FECD1 (136800).

Nomenclature

The late-onset form of Fuchs endothelial corneal dystrophy mapping to chromosome 5q33.1-q35.2 is referred to in OMIM as FECD5. Some references in the literature (e.g., Riazuddin et al., 2010) have used the designation 'FCD3 locus' to refer to the genetic locus for FECD on chromosome 5.

Clinical Features

Riazuddin et al. (2009) examined 17 members of a 3-generation family segregating autosomal dominant late-onset FECD and identified 10 affected individuals. Onset of disease occurred at approximately 40 years of age. The severity of disease was relatively milder and progression of disease was slower compared to previously studied FECD families (FECD2, 610158 and FECD3, 613269).

Mapping

Riazuddin et al. (2009) performed a genomewide linkage scan in 17 individuals from a large 3-generation family segregating autosomal dominant late-onset FECD in which linkage had been excluded to COL8A2 (120252) and the FECD2 and FECD3 loci. They localized the disease interval to the long arm of chromosome 5, obtaining a maximum 2-point lod score of 3.41 at D5S425 (theta = 0.00). Haplotype analyses defined a 27-Mb (29-cM) critical interval at 5q33.1-q35.2, flanked by D5S470 proximally and D5S2108 distally.