Genetics of Type 2 Diabetes: the Power of Isolated Populations
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Type 2 diabetes (T2D) affects millions of people worldwide. Improving the understanding of the underlying mechanisms and ultimately improving the treatment strategies are, thus, of great interest. To achieve this, identification of genetic variation predisposing to T2D is important. A large number of variants have been identified in large outbred populations, mainly from Europe and Asia. However, to elucidate additional variation, isolated populations have a number of advantageous properties, including increased amounts of linkage disequilibrium, and increased probability for presence of high frequency disease-associated variants due to genetic drift. Collectively, this increases the statistical power to detect association signals in isolated populations compared to large outbred populations. In this review, we elaborate on why isolated populations are a powerful resource for the identification of complex disease variants and describe their contributions to the understanding of the genetics of T2D.
KeywordsType 2 diabetes Isolated populations Linkage disequilibrium Genetic drift Genome-wide association study Statistical power
The Novo Nordisk Foundation Center for Basic Metabolic Research is an independent Research Center at the University of Copenhagen partially funded by an unrestricted donation from the Novo Nordisk Foundation (www.metabol.ku.dk). MKA was supported by a research grant from the Danish Diabetes Academy supported by the Novo Nordisk Foundation.
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Conflict of Interest
Mette Korre Andersen, Casper-Emil Tingskov Pedersen, Ida Moltke, Torben Hansen, Anders Albrechtsen, and Niels Grarup declare that they have no conflict of interest.
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This article does not contain any studies with human or animal subjects performed by any of the authors.
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