Familial Steep Corneas in Posterior Polymorphous Corneal Dystrophy 3 Due to a Novel ZEB1 Gene Mutation.

Abstract

Purpose: To present 4 family members with posterior polymorphous corneal dystrophy (PPCD), nonkeratoconic steep corneas, and myopia caused by a previously unknown genetic alteration in the ZEB1 gene.

Methods: Ophthalmic examinations and corneal curvature analyses were performed for all patients. Whole-exome targeted gene panel sequencing was performed for 1 patient. Pathogenic variant confirmation and segregation of the variant were performed for all 4 patients using Sanger sequencing.

Results: A mother and her 3 children presented with bilateral diffuse corneal opacities, vesicular aggregates at the Descemet membrane level, and endothelial stippling, compatible with the diagnosis of PPCD. All patients had steeper than average keratometry readings with normal globe axial lengths and refractive moderate to extremely high myopia, ranging from -2 to -16.5 diopters (spherical equivalent). The younger patients had more severe findings, with the youngest, an 11-month-old girl, presenting with keratometry readings of 66.72 × 69.48 @ 132 degrees and 66.10 × 67.32 @ 34 degrees in the right and left eyes, respectively. The ZEB1:c.794-1G>A; chr10-31809053G>A; NM_001174096.2 mutation was detected in all patients.

Conclusions: We describe a novel ZEB1 mutation associated with PPCD, nonkeratoconic steep corneas, and myopia. PPCD3 should be considered not only as an endothelial pathology but also as an ectatic disorder and should be ruled out in young children presenting with high myopia.