X-linked retinitis pigmentosa GTPase regulator-interacting protein 1 is a protein in the ciliary transition zone that in humans is encoded by the RPGRIP1 gene. RPGRIP1 is a multi-domain protein containing a coiled-coil domain at the N-terminus, two C2 domains and a C-terminal RPGR-interacting domain (RID). Defects in the gene result in the Leber congenital amaurosis (LCA) syndrome and in the eye disease glaucoma.