Recently RBCD, together with lattice corneal dystrophy type I (LCDI), granular corneal dystrophy (CDGG1) and Avellino stromal dystrophy (ASD), all mapped on 5q31, were found to be associated to four different mutations in the beta ig-h3 gene which codify for kerato-epithelin.
Screening all 17 exons of TGFB1 in the proband identified a single missense mutation (C1710T) in exon 12, consistent with the diagnosis of granular corneal dystrophy.
Among 24 clinical GCD patients, the proportion of R124H, R555Q, R124L, R555W and R124C were 37.5%, 16.7%, 25.0%, 20.8% and 0%, respectively, and 2 patients had been diagnosed with GCD according to the opacities thriving after LASIK (R124H) and PRK (R555W).
KC can co-exist with GCD.The missense mutation (c.370G > A) in the TGFBI gene and insert mutation (c.1456-1457ins GAT) in the KRT12 gene were identified in a 23-year-old male patient with concurrent KC and GCD.
We show here that the Arg555Trp mutant of the fourth fasciclin 1 (FAS1-4) domain of the protein (TGFBIp/keratoepithelin/βig-h3), associated with granular corneal dystrophy type 1, is significantly less susceptible to proteolysis by thermolysin and trypsin than the WT domain.
Cell adhesion assays demonstrated that heterozygous and homozygous GCD II PCFs strongly attached to collagen-I, collagen-IV, fibronectin, and laminin, compared with wild-type cells.Conclusions.