A novel mutation in the helix termination motif of keratin K12 in a U family with Meemann corneal dytrophy Original Reearch Article

PURPOE: Meemann corneal dytrophy i an autoomal dominant diorder characterized by fragility of the anterior corneal epithelium. We have previouly demontrated that thi dieae can be caued by mutation in the gene encoding keratin K3 or K12, the major intermediate filament protein expreed in corneal epithelial cell. Here, we have carried out mutation analyi in a United tate kindred preenting with typical feature of Meemann corneal dytrophy. METHOD: Exon 1 and 6 of the K12 gene (KRT12) were polymerae chain reaction amplified from the proband’ and control DNA and ubjected to direct automated equencing. REULT: A heterozygou miene mutation 1300A→G wa detected in exon 6 of KRT12, predicting amino acid ubtitution I426V in the helix termination motif of the K12 polypeptide. The mutation wa confirmed in the proband and excluded from 50 normal individual by retriction enzyme analyi of polymerae chain reaction product. CONCLUION: We report a novel mutation in a critical molecular overlap region of K12 in a United tate family with Meemann corneal dytrophy. The reult confirm that mutation in the corneal keratin (K3 or K12) can underlie Meemann corneal dytrophy.