GENETICS OF MYOCLONIC AND MYOCLONUS EPILEPSIES

Mendelian forms of benign myoclonic epilepsies where a chromosomal loc us has been defined include (1) the autosomal dominant (AD) juvenile m yoclonic epilepsy (JME) in chr. 6p11, (2) the autosomal dominant child hood absence epilepsy which evolves to JME in chr. 1p, (3) familial ad ult myoclonic epilepsy of Yasuda and Inazuki, and (4) possibly JME wit hin the idiopathic generalized epilepsy susceptibility gene in chr. 8 reported by Zara et al (1995). Other myoclonic epilepsy syndromes with onset in the first year of life (Aicardi's Neonatal (Early) Myoclonic Encephalopathy, West's Syndrome, Dravet's Severe Myoclonic Epilepsy, and Dravet's Benign Myoclonic Epilepsy of Infancy), in early childhood (Lennox-Gastaut-Dravet Syndrome, Myoclonic Variant of Lennox Gastaut Dravet Syndrome, Myoclonic-Astatic Epilepsy of Doose, Benign Myoclonic Epilepsies (BME), or even in late childhood (Childhood Absence Epilep sy with myoclonias, vs. Myoclonic Absence Epilepsy) are probably genet ically complex diseases. Amongst the progressive myoclonus epilepsy sy ndromes, specific mutations have already been defined in Unverricht Lu ndborg disease, ceroid lipofuscinoses 3 or Spielmayer Voight syndrome within Battens disease, sialidosis, dentadorubropallidoluysian atrophy and the mitochondrial syndrome MERRF. Most recently our laboratories established the locus for Lafora's disease in chr. 6q and results are speadily moving towards the definition of its mutation. (C) 1996 Wiley -Liss, Inc.