Genetik und Epigenetik des Typ-2-Diabetes – Die verschiedenen Ebenen der Genregulation

Genetische Prädisposition, d. h. das Vorhandensein bestimmter Genvarianten, Ernährung und körperliche Aktivität sind Kernelemente, die das Auftreten eines Typ-2-Diabetes (T2D) beeinflussen. Ernährung und körperliche Aktivität beeinflussen nicht nur direkt den Stoffwechsel, sondern können auch über epigenetische Mechanismen zu langfristigen Änderungen in der Expression stoffwechselrelevanter Gene führen. Zahlreiche Zwillingsstudien zeigten, dass die genetische Prädisposition eine wesentliche Rolle in der Diabetes-Suszeptibilität spielt. Während die klassische Genetik nach Veränderungen in der DNA-Basensequenz sucht, die sich sowohl auf die Genregulation als auch auf die Struktur der durch die Gene kodierten Proteine auswirken können, untersucht die Epigenetik Faktoren, die sich ohne Sequenzveränderung auf die Genexpression auswirken. Mit der Erforschung der genetischen und epigenetischen Grundlagen des T2D wollen Wissenschaftler des Deutschen Zentrums für Diabetesforschung (DZD) dazu beitragen, spezifischere Diagnosen durch Unterteilung der Krankheit in Subklassen zu ermöglichen. Neue Erkenntnisse auf diesem Gebiet bieten daher große Möglichkeiten, die T2D Prädiktion, Prävention sowie insbesondere die individualisierte Behandlung von Diabetikern zu verbessern.

The onset of type 2 diabetes is strongly associated with variations in different susceptibility genes. Besides sequence variations of these genes, epigenetic modulations as a second layer of gene regulation have come into focus, indicating a direct interaction between nutrition, physical activity and gene regulation. How both, genetic and epigenetic variations can be used in prediction, prevention and therapy, especially personalized treatment, is currently investigated.

Key words

epigenetics - genetics - type 2 diabetes - gene regulation - methylation

• Literatur

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