A new mutation (A546T) of the βig-h3 gene reponible for a French lattice corneal dytrophy type IIIA

PURPOE: To characterize the βig-h3 gene defect in a French family affected with lattice corneal dytrophy type IIIA (LCDIIIA). METHOD: Hitologic examination wa performed from corneal button of two patient. Genomic DNA wa extracted from leukocyte, and exon of the βig-h3 gene were amplified by polymerae chain reaction to be directly equenced. REULT: Numerou depoit were evident in the troma and beneath the Bowman membrane, which had all the feature of amyloid depoit. Analyi of exon 12 revealed a heterozygou G to A tranition on codon 546. CONCLUION: In contrat to Japanee patient, thee French patient affected with LCDIIIA carry a ditinct mutation of the βig-h3 gene (A546T intead of P501T). Therefore, it i unclear whether different mutation could reult in the ame dytrophy or whether we are dealing with clinical heterogeneity of LCDIIIA.