Genetik der Adipositas

Zusammenfassung

Die Varianz des Körpergewichtes wird durch erbliche Faktoren mitbestimmt. Molekulargenetische Studien konnten jedoch bisher nur einen kleinen Teil der Variabilität des BMI erklären. Monogene Formen der Adipositas sind sehr selten. Dabei kann der Wegfall eines einzigen Genprodukts zu extremer Adipositas führen. Ein komplexes Zusammenspiel vieler Genvarianten trägt zum BMI bei (polygene Adipositas). Dabei ist der Beitrag jeder einzelnen Variante zum Körpergewicht eher gering. In einer groß angelegten Meta-Analyse konnten kürzlich 97 polygene Varianten identifiziert werden, die mit Adipositas assoziiert sind. Neben den genomischen Varianten spielen auch epigenetische Mechanismen bei der Gewichtsregulation eine Rolle. Die epigenetische Ausstattung eines Menschen kann sich im Laufe des Lebens verändern. Sie kann als Schnittstelle zwischen genetischen und umweltbedingten Einflüssen angesehen werden. Es ist vorstellbar, dass in der Zukunft genetische und epigenetische Marker eingesetzt werden können, um eine Prädisposition zur Adipositas zu erkennen und ggf. auch die Therapie zu verbessern.

Summary

The variance of body weight is heritable. Molecular genetic findings so far only explained a small part of the variability of the BMI. Monogenic obesity is rare. Here, the loss of a single gene product leads to extreme obesity. A complex interplay of several genetic variants contributes to the BMI (polygenic obesity). The contribution of single variants to the body weight is small. A large meta-analysis identified 97 polygenic variants associated with obesity. Besides genetic variants, epi-genetic mechanisms play a role in weight regulation. The epigenetic landscape can change during lifetime. It acts as in interface between genetic and environmental influences. In the future, genetic and epigenetic markers could be used to detect predisposition for obesity and potentially improve therapy.

Schlüsselwörter

Adipositas - Erblichkeit - monogen - polygen - Hauptgeneffekt

Keywords

Obesity - heritability - monogenic - polygenic - major gene effect

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