Coexistence of Congenital Hereditary Endothelial Dystrophy and Fuchs Endothelial Corneal Dystrophy Associated With SLC4A11 Mutations in Affected Families.

Abstract

To evaluate parents of probands affected with autosomal recessive congenital hereditary endothelial dystrophy (CHED) for clinical signs of Fuchs endothelial corneal dystrophy (FECD) and to determine the genotypes of the SLC4A11 gene in the probands and their parents. This study involved 9 patients affected with CHED from 8 families. The parents of such probands were examined to investigate for possible signs of FECD although they did not present with any visual complaints. Blood samples were collected after obtaining consent, from all 9 cases and the parents of each proband, for genetic analysis. Genomic DNA isolated from blood leukocytes was used for genetic analysis. Screening of the coding regions of the SLC4A11 gene for mutations was carried out by standard procedures using polymerase chain reaction (PCR) amplification and sequencing. Sequences were checked against the human SLC4A11 reference sequence to detect alterations and in normal control samples available in the laboratory. The probands had characteristic signs of CHED, whereas one of the parents of each of the probands showed early signs of FECD, characterized by the presence of guttae in the central cornea corroborative with the diagnosis of FECD, and were otherwise asymptomatic at that time. The CHED-affected probands were homozygous for various SLC4A11 mutations, and their parents were heterozygous for the same. The mutations included missense mutations in 6 probands and nonsense mutations in 2 cases. Heterozygosity for SLC4A11 mutations in the parents of children with autosomal recessive CHED appears to be a risk factor for the development of FECD in these cases.