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Linkage disequilibrium due to random genetic drift*

Published online by Cambridge University Press:  14 April 2009

Tomoko Ohta
Affiliation:
National Institute of Genetics, Mishima, Japan
Motoo Kimura
Affiliation:
National Institute of Genetics, Mishima, Japan
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The behaviour of linkage disequilibrium between two segregating loci in finite populations has been studied as a continuous stochastic process for different intensity of linkage, assuming no selection. By the method of the Kolmogorov backward equation, the expected values of the square of linkage disequilibrium z2, and other two quantities, xy(1 − x) (1 − y) and z(1 − 2x) (1 − 2y), were obtained in terms of T, the time measured in Ne as unit, and R, the product of recombination fraction (c) and effective population number (Ne). The rate of decrease of the simultaneous heterozygosity at two loci and also the asymptotic rate of decrease of the probability for the coexistence of four gamete types within a population were determined. The eigenvalues λ1, λ2 and λ3 related to the stochastic process are tabulated for various values of R = Nec.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1969

References

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