Rapid adaptation to malaria facilitated by admixture in the human population of Cabo Verde
Abstract
Humans have undergone large migrations over the past hundreds to thousands of years, exposing ourselves to new environments and selective pressures. Yet, evidence of ongoing or recent selection in humans is difficult to detect. Many of these migrations also resulted in gene flow between previously separated populations. These recently admixed populations provide unique opportunities to study rapid evolution in humans. Developing methods based on distributions of local ancestry, we demonstrate that this sort of genetic exchange has facilitated detectable adaptation to a malaria parasite in the admixed population of Cabo Verde within the last ~20 generations. We estimate the selection coefficient is approximately 0.08, one of the highest inferred in humans. Notably, we show that this strong selection at a single locus has likely affected patterns of ancestry genome-wide, potentially biasing demographic inference. Our study provides evidence of adaptation in a human population on historical timescales.
Data availability
Scripts for analyses, simulations, and to reproduce figures can be found at https://github.com/agoldberglab/CV_DuffySelection . Sampling consent forms from original study do not allow for public release of genotype data. Inferred local ancestry information can be found at https://doi.org/10.5281/zenodo.4021277.
Article and author information
Author details
Funding
National Institutes of Health (R35 GM133481)
- Amy Goldberg
National Institutes of Health (F32 GM139313)
- Katharine L Korunes
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Hamid et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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