Linkage Disequilibrium: Ancient History Drives the New Genetics

Department of Biostatistics, School of Public Health, University of Michigan, Ann Arbor, MI, USA.
Human Heredity (Impact Factor: 1.47). 02/2005; 59(2):118-24. DOI: 10.1159/000085226
Source: PubMed


This brief review provides a summary of the biological causes of genetic association between tightly linked markers--termed linkage disequilibrium--and unlinked markers--termed population structure. We also review the utility of linkage disequilibrium data in gene mapping in isolated populations, in the estimation of recombination rates and in studying the history of particular alleles, including the detection of natural selection. We discuss current understanding of the extent and patterns of linkage disequilibrium in the genome, and its promise for genetic association studies in complex disease. Finally, we highlight the importance of using appropriate statistical procedures, such as the false discovery rate, to maximize the chances of success in large scale association studies.

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Available from: Thomas Nichols, Oct 13, 2015
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    • "The power of an association test is the probability of detecting a " true " effect. Besides LD patterns and extent in the population , the efficiency of association studies largely depends on the ability to distinguish between LD due to physical linkage and LD due to other evolutionary forces (Abecasis et al. 2005; Flint-Garcia et al. 2003; Gupta et al. 2005). One of the main hurdles for using association mapping to dissect the genetic architecture of complex traits in plants is the risk of false positives. "
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