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Asymmetric introgression reveals the genetic architecture of a plumage trait.

ABSTRACT: Genome-wide variation in introgression rates across hybrid zones offers a powerful opportunity for studying population differentiation. One poorly understood pattern of introgression is the geographic displacement of a trait implicated in lineage divergence from genome-wide population boundaries. While difficult to interpret, this pattern can facilitate the dissection of trait genetic architecture because traits become uncoupled from their ancestral genomic background. We studied an example of trait displacement generated by the introgression of head plumage coloration from personata to alba subspecies of the white wagtail. A previous study of their hybrid zone in Siberia revealed that the geographic transition in this sexual signal that mediates assortative mating was offset from other traits and genetic markers. Here we show that head plumage is associated with two small genetic regions. Despite having a simple genetic architecture, head plumage inheritance is consistent with partial dominance and epistasis, which could contribute to its asymmetric introgression.

SUBMITTER: Semenov GA

PROVIDER: S-EPMC7884433 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Asymmetric introgression reveals the genetic architecture of a plumage trait.

Semenov Georgy A GA Linck Ethan E Enbody Erik D ED Harris Rebecca B RB Khaydarov David R DR Alström Per P Andersson Leif L Taylor Scott A SA

Nature communications 20210215 1

Genome-wide variation in introgression rates across hybrid zones offers a powerful opportunity for studying population differentiation. One poorly understood pattern of introgression is the geographic displacement of a trait implicated in lineage divergence from genome-wide population boundaries. While difficult to interpret, this pattern can facilitate the dissection of trait genetic architecture because traits become uncoupled from their ancestral genomic background. We studied an example of t ...[more]

PMID: 33589637

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Dataset Information

Asymmetric introgression reveals the genetic architecture of a plumage trait.

Publications

Asymmetric introgression reveals the genetic architecture of a plumage trait.

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