Purpose: To assess the involvement of BIGH3 in corneal dystrophies (CD) with an autosomal dominant trait, in patients referred to a hospital in the Kyushu district of Japan.
Methods: Forty-five CD patients from 44 families were studied. Genomic DNA was extracted from peripheral blood, and exons 4 and 12 of the BIGH3 gene were amplified by polymerase chain reaction followed by direct sequencing.
Results: In exon 4, an R124H mutation associated with Avellino corneal dystrophy (ACD) was found in 39/44 families (86.4%) and an R124C mutation associated with lattice corneal dystrophy type 1 (LCD1) was detected in 2/44 families (4.5%). In exon 12, an R555W mutation associated with granular corneal dystrophy (GCD) was detected in 4/44 families (9.1%).
Conclusions: Codons R124 and R555 of the BIGH3 gene represent mutational hotspots in the genomes of Japanese patients with autosomal-dominant CD.