Advanced late-onset retinitis pigmentosa with dominant-acting D477G RPE65 mutation is responsive to oral synthetic retinoid therapy.

Families with D477G variant have been identified in Ireland, the UK, France, the USA and Canada. Effects of single 7-day oral retinoid supplementation lasted at least 6 months, possibly giving visual benefit throughout remaining life in patients with advanced disease, where gene therapy is unlikely to prove beneficial.