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Detecting range expansions from genetic data.

ABSTRACT: We propose a method that uses genetic data to test for the occurrence of a recent range expansion and to infer the location of the origin of the expansion. We introduce a statistic ? (the directionality index) that detects asymmetries in the 2D allele frequency spectrum of pairs of population. These asymmetries are caused by the series of founder events that happen during an expansion and they arise because low frequency alleles tend to be lost during founder events, thus creating clines in the frequencies of surviving low-frequency alleles. Using simulations, we show that ? is more powerful for detecting range expansions than both FST and clines in heterozygosity. We also show how we can adapt our approach to more complicated scenarios such as expansions with multiple origins or barriers to migration and we illustrate the utility of ? by applying it to a data set from modern humans.

SUBMITTER: Peter BM

PROVIDER: S-EPMC4282923 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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Detecting range expansions from genetic data.

Peter Benjamin M BM Slatkin Montgomery M

Evolution. 20130827 11

We propose a method that uses genetic data to test for the occurrence of a recent range expansion and to infer the location of the origin of the expansion. We introduce a statistic ψ (the directionality index) that detects asymmetries in the 2D allele frequency spectrum of pairs of population. These asymmetries are caused by the series of founder events that happen during an expansion and they arise because low frequency alleles tend to be lost during founder events, thus creating clines in the ...[more]

PMID: 24152007

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