RPGR and retinitis pigmentosa 1: RPGR has also been implicated in the trafficking or quality control of membrane proteins moving to/from the OS, since rod and cone opsins are mislocalised to the IS or plasma membrane in a variety of CC transport mutants (e.g. kinesin-2, intraflagellar transport or IFT proteins) and RP/LCA mouse models (Bbs2, Ahi1, Rp1, Rpgrip1, Cep290 mice), including several RPGR disease models.