The spectrum of beta ig-h3 gene mutations in Japanese patients with corneal dystrophy

Purpose, This study was undertaken to identify beta ig-h3 gene mutations in Japanese patients with granular corneal dystrophy (GCD), Avellino corneal dystrophy (ACD), lattice corneal dystrophy (LCD), and Reis-Bucklers' cornea l dystrophy (RBCD). R124H, R124C, R555W, and R555Q mutations have been repo rted in Europe to cause ACD, LCD type I, GCD, and RBCD, respectively. Metho ds. In total, 91 Japanese patients who bad been clinically diagnosed with G CD, LCD, or RBCD were investigated to determine whether they had mutations in the beta ig-h3 gene. Genomic DNA was amplified using the polymerase chai n reaction and analyzed using single-strand conformation polymorphism techn iques. Mutations were identified using the direct sequencing method. Result s. In 68 unrelated patients who had been diagnosed with GCD, 62 patients (9 1%) were found to have the R124H mutation, which has been reported to cause ACD, whereas only six patients (9%) had the R555W mutation. In LCD patient s, 10 patients with type I disease had the R124C mutation, and 10 patients with type IIIA disease had a P501T mutation. One patient with atypical LCD had an L527R mutation. In two patients with RBCD, one had an R555Q mutation and the other patient with geographic opacities was found to have an R124L mutation. Conclusions. Depending on the specific mutation in the beta ig-h 3 gene, the phenotypes of corneal dystrophy may differ. Our results indicat e that assay of mutations in the beta ig-h3 gene is required to establish a correct diagnosis.