Interestingly, in mice, the RPGRORF15 (the photoreceptor-specific ORF15 variant of retinitis pigmentosa GTPase regulator) implicated in retinal dystrophy actually localizes to connecting cilia of photoreceptors and is glutamylated by TTLL5 in vivo (Rao et al., 2016). Here, RPGR is linked to inherited retinal dystrophy.