Discussion
RP
DISEASE, RARE DISEASE
This study clearly demonstrates the variety of severities and progression rates that occur in RP, based on a well-documented cohort of patients with RP with longitudinal data. Having determined a molecular cause of disease for 73% of all participants (587 out of 799) evaluated, we also demonstrate the success of what may be the oldest DNA biobanking effort for this rare disease. Combining this high-quality phenotype and genotype data improves our understanding of the severity and progression of various RP genetic subtypes. These data can be useful both for prognostic information for patients, as well as for planning patient selection and endpoints for interventional clinical trials. We also found that in contrast to the original reports, updated analyses did not show a benefit for vitamin A supplementation in reducing progression of disease for patients with RP.