Epilepsy is a clinically and genetically heterogeneous group of disorders characterized by epileptic seizures and other symptoms of neurological problems. Epilepsy can be caused by strokes, brain tumors, head injuries, structural brain abnormalities, brain infections and genetic syndromes.
The epilepsies can be classified into three classes: genetic generalized, focal and encephalopathic epilepsies, with several specific disorders within each class. The genetic generalized epilepsy syndromes include juvenile myoclonic epilepsy and childhood absence epilepsy among others. Focal epilepsy syndromes include temporal lobe epilepsy, autosomal dominant nocturnal frontal lobe epilepsy and autosomal dominant epilepsy with auditory features. Epileptic encephalopathies are severe, early onset conditions characterized by refractory seizures, developmental delay or regression associated with ongoing epileptic activity, and generally poor prognosis.
Epilepsy is often a concurrent condition in individuals with intellectual disability, autism or schizophrenia.
Genetic factors are relevant in the development of epilepsy. Most genes being implicated in epilepsy are involved in dysfunction or dysregulation of ion channels.
Indications for genetic testing:
1. Confirmation of clinical diagnosis
2. Testing of at risk family members for known mutations
3. Prenatal diagnosis for known familial mutations
4. Genetic counseling
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