Abstract
Epilepsy is a group of neurological disorders characterized by an increase of the neuronal excitability that causes autolimited recurrent convulsions in absence of precipitating factors. The idiopathic epilepsy is related to age and usually it has good answer to the treatment and can present Mendelian or complex inheritance. According to the type of convulsion, the idiopathic epilepsy is subdivided in generalized idiopathic epilepsy and partial idiopathic epilepsy. There are four main types of generalized idiopathic epilepsy: juvenile mioclonics epilepsies, childhood and juvenile absence epilepsy and grand mal of waking up.
Recently several genes related by ligament and association studies are mapping; this way have been identified, more than 15 autosomal genes and one mitochondrial. One hopes that the identification of genes responsible for Mendelian forms of common types will help to recognize the genes of susceptibility. Unlike most of the cases of generalized idiopathic epilepsy, the generalized epilepsy with febrile seizures plus presents monogenic, autosomal dominant inheritance, with incomplete penetrance. Generalized seizures during fever episodes (febrile seizures) happen in 2-5 percent of children under six years. Of these, near five percent develop later in the life nonfebrile seizures or epilepsy. Four genes have been identified causes generalized epilepsy with febrile seizures plus: SCN1B (GEFSP1), SCN1A (GEFSP2), GABRG2 (GEFSP3) y SCN2A (GEFSP4). In addition to this four genes described in generalized epilepsy with febrile seizures plus also mutations in another gene associated with febrile seizures have been identified. This study was initiated in a great family of Japanese origin with febrile convulsions and soon 39 additional families confirmed ligament to the chromosomic region 5q14-q15 (FEB4).
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