Intellectual disability or developmental delay was reported in 12 patients with RPGRIP1 disease (Zernant et al., 2005; Khan et al., 2013, 2014; Abouzeid et al., 2016; Jinda et al., 2017; Sanchez-Navarro et al., 2018; Jespersgaard et al., 2019; Miyamichi et al., 2019). The gene discussed is RPGRIP1; the disease is Global developmental delay.