Rate of Progression in EYS Related Retinal Degeneration

This natural history study of patients with EYS mutations will accelerate the development of outcome measures for clinical trials. Sensitive, reliable outcome measures of retinal degeneration will greatly facilitate development of treatments for retinitis pigmentosa due to EYS mutations. Together these approaches are expected to have an impact on understanding EYS-related retinal degeneration, developing experimental treatment protocols, and assessing their effectiveness. The goals and expected impact of this natural history study are to: 1. Describe the natural history of retinal degeneration in patients with biallelic mutations in the EYS gene 2. Identify sensitive structural and functional outcome measures to use for future multicenter clinical trials in EYS-related retinal degeneration 3. Identify well-defined subpopulations for future clinical trials of investigative treatments for EYS-related retinal degeneration Study Objectives The primary objectives of the natural history study are to: 1. Characterize the natural history of retinal degeneration associated with biallelic pathogenic mutations in the EYS gene over 4 years, as measured using functional, structural, and patient-reported outcome measures 2. Investigate whether structural outcome measures can be validated as surrogates for functional outcomes in individuals with biallelic pathogenic mutations in the EYS gene 3. Evaluate possible risk factors (genotype, phenotype, environmental, and comorbidities) for progression of the outcome measures at 4 years in individual with biallelic pathogenic mutations in the EYS gene 4. Evaluate variability and symmetry of left and right eye outcomes over 4 years in individuals with biallelic pathogenic mutations in the EYS gene