DIFFUSE RETINAL VASCULAR LEAKAGE AND CONE-ROD DYSTROPHY IN A FAMILY WITH THE HOMOZYGOUS MISSENSE C.1429G>A (P.GLY477ARG) MUTATION IN CRB1.

Abstract

To describe a specific cone-rod dystrophy phenotype in a family with the homozygous c.1429G>A; p.Gly477Arg mutation in CRB1. The detailed phenotype of subjects with this specific mutation has not been described previously. Clinical examination included full-field electroretinography and high-resolution and widefield retinal imaging and uveitis workup. Molecular genetic analysis included next-generation sequencing of known retinal dystrophy genes and Sanger sequencing for segregation analysis. Three affected male siblings (26, 16, and 8 years old) were diagnosed with cone-rod dystrophy, featuring bilateral macular hypoautofluorescent lesions. In addition, the eldest brother was found to have retinal vascular leakage throughout the retina without telangiectasia. Uveitis laboratory workup was unremarkable. The homozygous c.1429G>A; p.Gly477Arg mutation in CRB1 was found to segregate with disease in this family. To the best of our knowledge, diffuse vascular leakage without telangiectasia or exudation, with bull's eye maculopathy, has not been reported previously in CRB1-cone rod dystrophy. This expands the phenotype complexity associated with CRB1 mutations and confirms that dystrophies associated with mutations in this gene may appear with features of uveitis.