De novo missense mutations in GRIN1 have previously been reported in patients with non-syndromic intellectual disability (Hamdan et al., 2011; Redin et al., 2014; Zhu et al., 2015; Lemke et al., 2016; Rossi et al., 2017), movement disorders (Ohba et al., 2015; Chen et al., 2017a; Zehavi et al., 2017), epileptic encephalopathy (Epi4K Consortium et al., 2013), and cerebral visual impairment (Bosch et al., 2016). The gene discussed is GRIN1; the disease is Epileptic encephalopathy.