Abstract
Purpose :
To describe two novel and previously unreported genetic variants in patients with CRB1-related retinal degenerations and increase the genotype-phenotype understanding of CRB1-related retinal degenerative diseases.
Methods :
Two probands with their families, were evaluated for progressive loss of central and peripheral vision. Multimodal imaging testing, including fundus photography, fundus autofluorescence (FAF), fluorescein angiography (FA), and optical-coherence tomography (OCT) was performed. Next generation panel sequencing (NGS) was utilized to explore underlying mutations.
Results :
In patient 1, NGS sequencing revealed a previously reported, pathogenic variant in the CRB1 gene (c.2842+5G>A), and a variant of unknown significance (c.4014T>A). Phenotypically, the patient demonstrated cystoid macular edema refractory to therapy. Patient 2 was found to be heterozygous for a sequence variant (c.2290C>T), documented to be causative for autosomal recessive retinitis pigmentosa or Leber congenital amaurosis, and heterozygous for a previously not reported sequence variant (c.1348T>C). Phenotypically, this patient demonstrated pigmentary degenerative changes with venous tortuosity, loss of retina pigment epithelium, and bilateral vasoproliferative tumors.
Conclusions :
This study adds a breadth of phenotypic understanding to genetic analysis in CRB1 related retinal degenerations. The newly described CRB1 variant mutation c.4014T>A may portend a poor prognosis for CME responsiveness to therapy. Genetic testing in an otherwise unexplained CME event may be useful to identify underlying CRB1 variants, which may alter the treatment plan and prognosis.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.