We and others subsequently showed 6/500 epileptic encephalopathy cases had de novo CHD2 mutations (Carvill et al., 2013; Epi4K Consortium et al., 2013; Suls et al., 2013; Lund et al., 2014), and recently showed that clinical photosensitivity was prominent in the rare CHD2-associated myoclonic encephalopathy (Thomas et al., 2015). The gene discussed is CHD2; the disease is Epileptic encephalopathy.