Establishing the validity of domestication genes using DNA from ancient chickens

Linus Girdland Flink, Richard Allen, Ross Barnett, Helena Malmstrom, Joris Peters, Jonas Eriksson, Leif Andersson, Keith Dobney, Greger Larson*

*Corresponding author for this work

Research output: Contribution to journalArticle

58 Citations (Scopus)
85 Downloads (Pure)

Abstract

Modern domestic plants and animals are subject to human-driven selection for desired phenotypic traits and behavior. Large-scale genetic studies of modern domestic populations and their wild relatives have revealed not only the genetic mechanisms underlying specific phenotypic traits, but also allowed for the identification of candidate domestication genes. Our understanding of the importance of these genes during the initial stages of the domestication process traditionally rests on the assumption that robust inferences about the past can be made on the basis of modern genetic datasets. A growing body of evidence from ancient DNA studies, however, has revealed that ancient and even historic populations often bear little resemblance to their modern counterparts. Here, we test the temporal context of selection on specific genetic loci known to differentiate modern domestic chickens from their extant wild ancestors. We extracted DNA from 80 ancient chickens excavated from 12 European archaeological sites, dated from similar to 280 B.C. to the 18th century A.D. We targeted three unlinked genetic loci: the mitochondrial control region, a gene associated with yellow skin color (beta-carotene dioxygenase 2), and a putative domestication gene thought to be linked to photoperiod and reproduction (thyroid-stimulating hormone receptor, TSHR). Our results reveal significant variability in both nuclear genes, suggesting that the commonality of yellow skin in Western breeds and the near fixation of TSHR in all modern chickens took place only in the past 500 y. In addition, mitochondrial variation has increased as a result of recent admixture with exotic breeds. We conclude by emphasizing the perils of inferring the past from modern genetic data alone.

Original languageEnglish
Pages (from-to)6184-6189
Number of pages6
JournalPNAS
Volume111
Issue number17
DOIs
Publication statusPublished - 29 Apr 2014

Keywords

  • selective sweep
  • breed formation
  • animal domestication
  • Gallus gallus
  • cultural history
  • dog domestication
  • regulatory mutation
  • breed
  • selection
  • origins
  • wheat
  • FGF4
  • pig

Cite this

Girdland Flink, L., Allen, R., Barnett, R., Malmstrom, H., Peters, J., Eriksson, J., Andersson, L., Dobney, K., & Larson, G. (2014). Establishing the validity of domestication genes using DNA from ancient chickens. PNAS, 111(17), 6184-6189. https://doi.org/10.1073/pnas.1308939110