Clinical Phenotypes of CDHR1-Associated Retinal Dystrophies.

Abstract

The retinal dystrophy phenotype associated with CDHR1 retinopathy is clinically heterogenous. In this study, we describe the clinical and molecular findings of a retinal dystrophy cohort (10 patients) attributed to autosomal recessive CDHR1 and report novel variants in populations not previously identified with CDHR1-related retinopathy. Seven patients had evaluations covering at least a three-year period. The mean age of individuals at first symptoms was 36 ± 8.5 years (range 5–45 years). Visual acuity at the last visit ranged from 20/20 to 20/2000 (mean LogMAR 0.8 or 20/125). Three clinical subgroups were identified: rod–cone dystrophy (RCD), cone–rod dystrophy (CRD), and maculopathy. Extinguished scotopic electroretinography responses were noted in the RCD patients. Macular involvement was noted in all patients and documented on color fundus photography, fundus autofluorescence, and optical coherence tomography. Notable asymmetry of the degree of macular atrophy was present in two patients. The possible association between CDHR1 variants and clinical findings was predicted using molecular modeling.