Among these genes, the RPGR gene, which was discovered two decades ago (Meindl et al., 1996, Roepman et al., 1996), is one of the most prevalent causative genes, accounting for approximately 16% of RP patients (Vervoort et al., 2000, Hartong et al., 2006, Jin et al., 2006a, Huang et al., 2015b). Here, RPGR is linked to retinitis pigmentosa 1.