Detecting the footprints of divergent selection in oaks with linked markers
Language
en
Article de revue
This item was published in
Heredity. 2012, vol. 109, n° 6, p. 361-371
Nature Publishing Group
English Abstract
Genome scans are increasingly used to study ecological speciation, providing a useful genome-wide perspective on divergent selection in the presence of gene flow. Here, we compare current approaches to detect footprints ...Read more >
Genome scans are increasingly used to study ecological speciation, providing a useful genome-wide perspective on divergent selection in the presence of gene flow. Here, we compare current approaches to detect footprints of divergent selection in closely related species. We analyzed 192 individuals from two interfertile European temperate oak species using 30 nuclear microsatellites from eight linkage groups. These markers present little intraspecific differentiation and can be used in combination to assign individual genotypes to species. We first show that different outlier detection tests give somewhat different results, possibly due to model constraints. Second, using linkage information for these markers, we further characterize the signature of divergent selection in the presence of gene flow. In particular, we show that recombination estimates for regions with outlier markers are lower than those for a control region, in line with a prediction from ecological speciation theory. Most importantly, we show that analyses at the haplotype level can distinguish between truly divergent (bi-directional) selection and positive selection in one of the two species, offering a new and improved method for characterizing the speciation process.Read less <
Keywords
Quercus
English Keywords
divergent selection
divergence hitchhiking
outlier detection
linkage disequilibrium
score tests
Origin
Hal imported