For example, a double concentric hyper-AF ring was first described in NR2E3-linked RP[197] and attributed to this mutation, but was thereafter also noted in USH2A-linked RP.[198] In a study by Trichonas et al, the pattern of peripheral UWF-FAF was noted to differ among patients with certain genetically confirmed RP mutations.[199] Distinct changes such as the double hyper-AF ring with USH2A or diffuse peripheral hypo-AF and dark appearance with USH2A or PRPH2/RDS mutations were demonstrated. The gene discussed is PRPH2; the disease is retinitis pigmentosa 1.