Recent studies have identified mutations in several genes, including SCN1A, SCN2A, SCN1B, STX1B, SLC2A1, GABRG2, CHD2, SYNGAP1, KIAA2022, NEXMIF, and SLC6A1, that can contribute to the phenotype of Doose syndrome (13–15). The gene discussed is CHD2; the disease is epilepsy with myoclonic atonic seizures.