Abstract
Purpose :
To report and characterize a novel phenotypic mutation in the collagen, type II, alpha 1 (COL2A1) gene, manifesting solely in the retina. COL2A1 mutations are typically associated with Stickler syndrome.
Methods :
Retrospective case study of a 64-year-old man with a generalized rod-cone degeneration. XomeDx test for 56 genes was performed by GeneDx on DNA isolated from whole blood lymphocytes. Identified variants were analyzed using Alamut software version 2.2 (Interactive Biosoftware, Rouen, France). Fundus short wavelength autoflourescence and SD-OCT were obtained using a Spectralis HRA+OCT (Heidelberg Engineering, Heidelberg, Germany).
Results :
A 64-year-old man presented by tertiary referral for evaluation of an unspecificed rod-cone dysfunction. Visual acuity was 20/800 bilaterally with normal intraocular tension and extraocular movements. The anterior segment was unremarkable on exam. On dilated fundus exam, a bulls-eye pattern of retinal pigment epithelium (RPE) atrophy, intraretinal pigment migration encroaching on the maculae, arterial attenuation, and pale optic discs were noted bilaterally. SD-OCT and fundus autofluorescence imaging corroborated exam findings, revealing extensive outer retinal thinning and RPE atrophy, respectively. Panel-based genetic testing revealed a c.4316C>T, p.(Thr1439Met) missense mutation in exon 53 of COL2A1, which was predicted to be pathogenic: Align GVGD (C0); SIFT, deleterious (0.02); MutationTaster, disease causing.
Conclusions :
Patients harboring the c.4316C>T, p.(Thr1439Met) mutation in COL2A1 may present with a non-syndromic retinal degeneration. This expands the phenotype of COL2A1-associated retinopathy, which typically occurs in the context of Stickler syndrome.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.