Dissecting the genetic basis of myoclonic-astatic epilepsy.

Herman Doose first described the generalized childhood epilepsy syndrome of myoclonic astatic epilepsy (MAE) in 1970, attributing a genetic cause from this first description. However, although the International League Against Epilepsy (ILAE) defined criteria for MAE in 1989, the diagnostic boundaries of the syndrome continue to be debated. Moreover, 40 years since Doose's first description of MAE, although a genetic predisposition is acknowledged and many studies have demonstrated familial aggregation of seizures within MAE families, the actual genetic determinants of MAE still remain unknown. Although initially thought to be within the same spectrum as severe myoclonic epilepsy of infancy, the exclusion of SCN1A mutations in non-generalized epilepsy with febrile seizures plus (GEFS+) MAE cases has confirmed the genetic distinction of MAE. In this critical review, we shall trace the historical evolution of concepts around MAE and its distinction from Lennox-Gastaut syndrome, review the described phenotypic features of MAE from updated studies that will allow its distinction from other overlap epilepsy syndromes, review the evidence of genetic influences and clues for genetic heterogeneity, and discuss strategies that may be helpful in elucidating the etiology of MAE in light of current genetic techniques.