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Honest Facts On My Hesperadin Triumph

This accounts for the congruent observation by Latta (1998) and Le Corre & Kremer (2003) that uniform selection on a multilocus trait results in elevated differentiation at QTL in comparison with neutral markers. The main expectations regarding the relative values of FST, FSTQ and QST for a multilocus trait can be roughly summarized as shown in Table?2. The limit put between ��weakly divergent�� and ��divergent�� selection, selleckchem based on the comparison of the variance of phenotypic optima with the neutral genetic variance among populations, will be difficult to establish in practice as the neutral variance among populations depends on both the total available variance for the trait and the joint effects of migration and drift. It must be emphasized that it is a relative notion: under identical environmental constraints, genetically isolated populations are more likely to experience ��weakly divergent�� selection. In cases where contrasted values of FST, FSTQ and Hesperadin QST are expected, for example, when gene flow is high and selection divergent (Table?2), the success of outlier-based detection methods will depend on the number of loci involved in the trait: for a small number of loci, FSTQ should be closer to QST than to FST, whereas for a high number of loci, FSTQ should be closer to FST. The effect of the number of loci as well as the effects of other attributes of the AZD2281 molecular weight genetic architecture of a quantitative trait not taken into account by simplified quantitative genetic model will now be described. Mathematically, for n quantitative trait loci, the genetic variance attributable to the variance of allelic frequencies can be as low as 1/n, the rest of the variance being accounted for by covariance. As shown by Latta (1998), there is a much greater influence of covariance on genetic differentiation when the trait is controlled by numerous loci each of small effects than when it is controlled by a few loci with large effects. Figure?3 illustrates the effect of the number of loci on FSTQ for a set of 25 populations connected by intermediate level of gene flow (Nm?=?1) under divergent local selection. These results were obtained using individual-based simulations as in our previous papers (Le Corre & Kremer 2003; Kremer & Le Corre 2011). Effects of alleles were drawn in a Gaussian distribution with variance adjusted to match the fixed value of the initial genetic variance (Table?1) and were smaller as the number of loci increased. Simulation results show that mean FSTQ values approach phenotypic differentiation only when the number of loci is <5. When the selected trait is controlled by 20 or more loci, genetic covariance is the main driver of genetic differentiation, and FSTQ became closer to the neutral differentiation FST than to QST.</div>
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