Idiopathic epilepsies are a heterogenous group of conditions characterized by different types of seizures, ages of onset, and EEG features. By definition, idiopathic epilepsies show no underlying cause other than a possible inherited predisposition. For most syndromes, especially the common ones, the mode of inheritance is complex rather than monogenetic. However, some rare idiopathic epilepsies show an autosomal dominant mode of inheritance, and genetic studies have been most successful in these diseases. Thus far, genes underlying the rare syndromes of autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE), benign familial neonatal convulsions (BFNC), and generalized epilepsy with febrile seizures plus (GEFS+) have been cloned. The first genes that were identified code for different types of ion channel proteins. Thus, it is likely that ion channels play an important role in the etiology of complex inherited forms of idiopathic epilepsies. A detailed under standing of the pathophysiological implications of these results could have important implications for the de velopment of target-specific antiepileptic drugs. NEUROSCIENTIST 5:295-301, 1999
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