Leu518Pro mutation of the βig-h3 gene causes lattice corneal dystrophy type I

PURPOSE: To describe a Japanese family with lattice corneal dystrophy type I, which segregates with a novel mutation, Leu518Pro of the beta ig-h3 gene. METHODS: DNA was extracted from leukocytes in four members (three affected and one unaffected) of a Japanese family with lattice corneal dystrophy type I. Exon 12 of the beta ig-h3 gene was amplified and analyzed with a molecular biologic method. Clinical data were also collected. RESULTS: Three generations of this family have been positively diagnosed with lattice corneal dystrophy, indicating autosomal dominant inheritance, We found a heterozygous point mutation that segregates with the disease phenotype. It was a single base-pair transition (CTG to CCG, Leu to Pro). CONCLUSION: Although it is extremely rare compared with the Arg124Cys mutation of the beta ig-h3 gene, Leu518Pro mutation of the beta ig-h3 also causes lattice corneal dystrophy type I. (Am J Ophthalmol 1999;128:104-106. (C) 1999 by Elsevier Science Inc, All rights reserved.).