RHO and retinal degeneration: While approximately 96 different mutated genes have been identified in patients with RP (RetNet; November 2019)1, mutations in rhodopsin (RHO) are the most common causes of RP, accounting for approximately 15% of all inherited human retinal degenerations (Chapple et al., 2001) and 30–40% of patients with the autosomal dominant form of the disease (Ferrari et al., 2011).