Zhu Xiaofeng, Wang Heming
Department of Population and Quantitative Health Sciences, Case Western Reserve University School of Medicine, Wolstein Research Building, 2103 Cornell Road, Cleveland, OH, 44106, USA.
Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, 02115, USA.
Methods Mol Biol. 2017;1666:505-525. doi: 10.1007/978-1-4939-7274-6_25.
Population of ethnic mixtures can be useful in genetic studies. Admixture mapping, or mapping by admixture linkage disequilibrium (MALD), is specially developed for admixed populations and can supplement traditional genome-wide association analyses in the search for genetic variants underlying complex traits. Admixture mapping tests the association between a trait and locus-specific ancestries. The locus-specific ancestries are in linkage disequilibrium (LD), which is generated by an admixture process between genetically distinct ancestral populations. Because of the highly correlated-locus specific ancestries, admixture mapping performs many fewer independent tests across the genome than current genome-wide association analysis. Therefore, admixture mapping can be more powerful because it reduces the penalty due to multiple tests. In this chapter, we introduce the theory behind admixture mapping and explain how to conduct the analysis in practice.
种族混合人群在基因研究中可能很有用。混合映射，即通过混合连锁不平衡（MALD）进行映射，是专门为混合人群开发的，并且可以在寻找复杂性状潜在遗传变异的过程中补充传统的全基因组关联分析。混合映射测试一个性状与特定基因座祖先之间的关联。特定基因座祖先处于连锁不平衡（LD）状态，这是由基因上不同的祖先群体之间的混合过程产生的。由于特定基因座祖先高度相关，混合映射在全基因组中进行的独立测试比当前的全基因组关联分析少得多。因此，混合映射可能更具效力，因为它减少了多重测试带来的惩罚。在本章中，我们介绍混合映射背后的理论，并解释如何在实践中进行分析。
