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We developed a novel method for efficiently estimating time-varying selection coefficients from genome-wide ancient DNA data. In simulations, our method accurately recovers selective trajectories and is robust to misspecification of population size. We applied it to a large data set of ancient and present-day human genomes from Britain and identified seven loci with genome-wide significant evidence of selection in the past 4500 yr. Almost all of them can be related to increased vitamin D or calcium levels, suggesting strong selective pressure on these or related phenotypes. However, the strength of selection on individual loci varied substantially over time, suggesting that cultural or environmental factors moderated the genetic response. Of 28 complex anthropometric and metabolic traits, skin pigmentation was the only one with significant evidence of polygenic selection, further underscoring the importance of phenotypes related to vitamin D. Our approach illustrates the power of ancient DNA to characterize selection in human populations and illuminates the recent evolutionary history of Britain.
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Deconstructing Eurocentrism in skin pigmentation research via the incorporation of diverse populations and theoretical perspectives
Abstract The evolution of skin pigmentation has been shaped by numerous biological and cultural shifts throughout human history. Vitamin D is considered a driver of depigmentation evolution in humans, given the deleterious health effects associated with vitamin D deficiency, which is often shaped by cultural factors. New advancements in genomics and epigenomics have opened the door to a deeper exploration of skin pigmentation evolution in both contemporary and ancient populations. Data from ancient Europeans has offered great context to the spread of depigmentation alleles via the evaluation of migration events and cultural shifts that occurred during the Neolithic. However, novel insights can further be gained via the inclusion of diverse ancient and contemporary populations. Here we present on how potential biases and limitations in skin pigmentation research can be overcome with the integration of interdisciplinary data that includes both cultural and biological elements, which have shaped the evolutionary history of skin pigmentation in humans.
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- Award ID(s):
- 1926075
- PAR ID:
- 10439972
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Evolutionary Anthropology: Issues, News, and Reviews
- Volume:
- 32
- Issue:
- 4
- ISSN:
- 1060-1538
- Page Range / eLocation ID:
- p. 195-205
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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