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Decomposing multilocus linkage disequilibrium.

Root Gorelick·Manfred D Laubichler
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Abstract

We present a mathematically precise formulation of total linkage disequilibrium between multiple loci as the deviation from probabilistic independence and provide explicit formulas for all higher-order terms of linkage disequilibrium, thereby combining J. Dausset et al.'s 1978 definition of linkage disequilibrium with H. Geiringer's 1944 approach. We recursively decompose higher-order linkage disequilibrium terms into lower-order ones. Our greatest simplification comes from defining linkage disequilibrium at a single locus as allele frequency at that locus. At each level, decomposition of linkage disequilibrium is mathematically equivalent to number theoretic compositions of positive integers; i.e., we have converted a genetic decomposition into a mathematical decomposition.

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AllelesBiological EvolutionEpistasis, GeneticGene FrequencyGenetic VariationLinkage DisequilibriumMathematicsModels, GeneticProbabilitySpecies SpecificityJournal Article

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Root Gorelick, Manfred D Laubichler. 2004. Decomposing multilocus linkage disequilibrium.. https://doi.org/10.1534/genetics.166.3.1581

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