Second order moments of segregating sites under variable population size

The identification of genomic regions which have been exposed to positive selection is a major challenge in population genetics. Since selective sweeps are expected to occur during environmental changes or when populations are colonizing a new habitat, statistical tests constructed on the assumption of constant population size are biased by the co-occurrence of population size changes and selection. In order to delimit this problem and gain better insights into demographic factors, theoretical results regarding the second order moments of segregating sites, such as the variance of segregating sites, have been derived. Driven by emerging genome-wide surveys, which allow the estimation of demographic parameters, a generalized version of Tajima's D has been derived which takes into account a previously estimated demographic scenario to test single loci for traces of selection against the null hypothesis of neutral evolution under variable population size.

Key Words: Drosophila melanogaster, Tajima's D, coalescent trees, second order moments, variable population size

This article has been cited by other articles:

				M. Teschke, O. Mukabayire, T. Wiehe, and D. Tautz Identification of Selective Sweeps in Closely Related Populations of the House Mouse Based on Microsatellite Scans Genetics, November 1, 2008; 180(3): 1537 - 1545. [Abstract] [Full Text] [PDF]

Online ISS 1091-6490
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