The Effects of Demographic History and Selection on Patterns of Polymorphism
نویسنده
چکیده
The effect of demographic history on patterns of polymorphism at a locus can seriously impede the detection of selection. Sliding window analysis of Tajima’s D was performed on sequence data available for Picea abies. The distribution of Tajima’s D was compared to coalescent simulations of different demographic scenarios. A growth model including some population differentiation was found to explain much of the deviation of the data from the distribution expected under the standard neutral theory. The effect of demographic models on tests of significance was examined using three functional candidate genes for budset in P. abies. It was found that incorporating the model into significance testing resulted in a considerable shift of significance cut-off values, demonstrating that this is an important factor when using coalescent analysis that has been often overlooked.
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