Clinical phenotype of posterior polymorphous corneal dystrophy in a family with a novel ZEB1 mutation

Purpose: To describe the clinical phenotype in a family with posterior polymorphous corneal dystrophy (PPCD) and a novel mutation in the ZEB1 gene. Methods: Clinical examination, anterior segment photography, specular microscopy and electrophysiological investigations were performed and quantified. Genomic DNA extracted from peripheral blood was sequenced for ZEB1 exons. Cosegregation of identified mutation with the disease status in the family was confirmed using polymerase chain reaction and restriction fragment length polymorphism. Results: Ocular examination was performed on five family members from two generations. Three had anomalies of the corneal endothelium that were consistent with PPCD. Endothelial cell counts ranged from 2306 to 2987 mm² (ref. 2000-4000 cells/mm²). No evidence of glaucoma or retinal abnormalities was observed. Extraocular abnormalities such as inguinal herniation, hydrocoele and possible bony or connective tissue anomalies were part of the disease spectrum in this family. Mutation analysis revealed a novel change in exon 5 of ZEB1 (c.672delA) that cosegregated with the affected disease status. Conclusion: The detailed clinical features of PPCD associated with a novel ZEB1 mutation are supportive of the previously proposed range of phenotype parameters. Further phenotype-genotype correlations may provide insights into the clinical variability and pathological processes affecting the corneal endothelium, Descemet's membrane, retinal photoreceptor function and extraocular tissues of some patients.