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arXiv · 0911.5672

Sample genealogies and genetic variation in populations of variable size

A. Eriksson·B. Mehlig·M. Rafajlovic·S. Sagitov
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Abstract

We consider neutral evolution of a large population subject to changes in its population size. For a population with a time-variable carrying capacity we have computed the distributions of the total branch lengths of its sample genealogies. Within the coalescent approximation we have obtained a general expression, Eq. (27), for the moments of these distributions for an arbitrary smooth dependence of the population size on time. We investigate how the frequency of population-size variations alters the distributions. This allows us to discuss their influence on the distribution of the number of mutations, and on the population homozygosity in populations with variable size.

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A. Eriksson, B. Mehlig, M. Rafajlovic, S. Sagitov. 2009-11-30. Sample genealogies and genetic variation in populations of variable size. https://doi.org/10.1534/genetics.103.018002

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