STXBP1 and infantile spasms: After the initial identification of mutations for cryptogenic West syndrome and Ohtahara syndrome (2), in the genes ARX, CDKL5, STXBP1, SLC25A22, SPTAN1, PLCb1, MAGI2, PNKP, SCN1A, numerous other mutated genes for West syndrome, Dravet syndrome and various other types of childhood-onset epilepsy have been found, revealing that a significant proportion of cryptogenic EOEEs are single-gene disorders (3–5).