Genetische Befunde bei Epilepsie und ihre Konsequenzen

Zusammenfassung

Epilepsien gehören zu den häufigsten neurologischen Erkrankungen und betreffen etwa 1% der Weltbevölkerung. Man unterscheidet nach der Ätiologie die symptomatischen Formen, die sekundär durch eine andere Krankheit, meist durch Hirnläsionen, hervorgerufen werden, sowie die idiopathischen Formen, die genetisch bedingt sind. Die Gendefekte bei den idiopathischen Epilepsien betreffen ganz überwiegend Ionenkanäle und verändern die Erregbarkeit von Nervenzellen oder die synaptische Übertragung. Dadurch kann das Auftreten epileptischer Anfälle gut erklärt werden. Die Erforschung der genetischen Defekte trug viel zum Verständnis die Pathophysiologie von Epilepsien bei und bildet die Grundlage für eine gezielte Entwicklung neuer Medikamente. Die Kenntnis des genetischen Befundes für den einzelnen Patienten ist in vielerlei Hinsicht hilfreich. Die diagnostische Sicherheit spielt für den Patienten psychologisch eine wichtige Rolle und erübrigt weitere diagnostische Maßnahmen. Die genetische Beratung in Bezug auf weitere Familienangehörige spielt eine wichtige Rolle, in manchen Fällen ist auch eine prädiktive Testung sinnvoll. Schließlich können die genetischen Befunde therapeutische Konsequenzen haben. Diese verschiedenen Aspekte werden in dem vorliegenden Artikel anhand von Beispielen dargelegt und diskutiert.

Summary

Epilepsy is one of the most common neurological disorders affecting about 1% of the world’s population. The underlying etiology distinguishes between symptomatic forms, based on a primary disease such as a cerebral lesion, and idiopathic forms with a genetic origin. The genetic defects known for idiopathic epilepsies mainly affect ion channels changing neuronal excitability or synaptic transmission, which can well explain the occurance of epileptic seizures. The identification of genetic alterations helps to better understand the pathophysiology of epilepsy which is the basis for the discovery of new anti-epileptic therapies. Knowledge of the genetic defect can be helpful for the individual patient in many aspects. It can be psychologically very important for a particular patient to be sure about the diagnosis and it can help to avoid further diagnostic procedures. Genetic counselling for family members of patients with idiopathic epilepsy can be very helpful, and in some cases a predictive testing is meaningful. Some of the genetic results are also relevant for therapeutic decisions. These different aspects are discussed in the present article for several examples.

Schlüsselwörter

Idiopathisch - Sequenzierung - Mutation - genetische Beratung

Keywords

Idiopathic - sequencing - mutation - genetic counselling

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