Interestingly, the very recent study of the Epi4K consortium revealed 1 additional case of a denovo mutation in GRIN2B in 1 of 115 individuals with epileptic encephalopathy ofLennox–Gastaut type (see Fig 1).12 The patient shows parallels to Patient 3 of our present study. The gene discussed is GRIN2B; the disease is Epileptic encephalopathy.