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GENETICS

Selection still shapes our genome

Nature Human Behaviour volume 5, pages 1600–1601 (2021)Cite this article

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A key question in human evolutionary genetics is whether and how natural selection has shaped the human genome. A new study by Song and colleagues uses GWAS data to examine evidence for the effects of polygenic adaptation in complex traits at different time scales.

Anatomically modern humans evolved in Africa and spread to a broad range of environments. We know that, following this expansion, biological adaptation has helped to enable humans to drink milk as adults, resist endemic pathogens and live in Arctic environments, among other phenotypes1, and there is also evidence suggesting that the interbreeding of anatomically modern humans with archaic species could have facilitated adaptation to specific environments2. However, it remains unclear whether selection has also had an effect on complex phenotypes that are associated with multiple genetic loci, each contributing in a small proportion to a phenotype. In a new study, Song and colleagues3 use the results from genome-wide association studies (GWAS) of 870 polygenic traits to conduct a comprehensive analysis of the selective pressures acting on these traits over time. Interestingly, the authors identify several traits that appear to be affecting human fertility and mating success, suggesting that, despite environmental changes in modern societies, there may be traits that are still under positive selection. When analysing the past 2,000 years of human evolution, they observe that a large proportion of the analysed traits carry signals of selective pressures. More intriguingly, their results suggest that diseases such as skin cancer or inflammatory bowel syndrome, and disorders such as attention deficit hyperactive disorder and anorexia nervosa, may be by-products of other positive selection events. Similarly, when comparing ancient DNA samples from Neolithic and hunter-gatherer populations of Europe and the Near East, Song and colleagues identify a large number of traits that show different selective pressures depending on ancestry, as well as genetic variants associated with diseases that show evidence of positive selection across the entirety of the Neolithic period (beginning approximately 10,000 years ago). Finally, when analysing the presence of ancient selective pressures in these traits, overall the authors find evidence of purifying selection (selective pressures erasing alleles that are deleterious) for genetic variants associated with most of the diseases they looked at. However, diseases and disorders such as primary sclerosing cholangitis, anorexia nervosa and atrial fibrillation show signals consistent with positive selection.

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References

  1. Fan, S., Hansen, M. E. B., Lo, Y. & Tishkoff, S. A. Science 354, 54–59 (2016).

    CAS  Article  Google Scholar 

  2. Racimo, F., Sankararaman, S., Nielsen, R. & Huerta-Sánchez, E. Nat. Rev. Genet. 16, 359–371 (2015).

    CAS  Article  Google Scholar 

  3. Song, W. et al. Nat. Hum. Behav. https://doi.org/10.1038/s41562-021-01231-4 (2021).

    Article  PubMed  Google Scholar 

  4. Laland, K. N., Odling-Smee, J. & Myles, S. Nat. Rev. Genet. 11, 137–148 (2010).

    CAS  Article  Google Scholar 

  5. Rinaldi, A. EMBO Rep. 18, 2094–2100 (2017).

    CAS  Article  Google Scholar 

  6. Templeton, A. R. Rambam Maimonides Med. J. 1, e0006 (2010).

    Article  Google Scholar 

  7. Stearns, S. C. & Medzhitov, R. Evolutionary Medicine (Sinauer Associates, 2015).

  8. Barghi, N., Hermisson, J. & Schlötterer, C. Nat. Rev. Genet. 21, 769–781 (2020).

    CAS  Article  Google Scholar 

  9. Field, Y. et al. Science 354, 760–764 (2016).

    CAS  Article  Google Scholar 

  10. Crouch, D. J. M. & Bodmer, W. F. Proc. Natl Acad. Sci. USA 117, 18924–18933 (2020).

    CAS  Article  Google Scholar 

  11. Abdellaoui, A. et al. Nat. Hum. Behav. 3, 1332–1342 (2019).

    Article  Google Scholar 

Download references

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Authors and Affiliations

  1. Population Genomics, Centre Nacional d’Anàlisi Genòmica (CNAG-CRG), Centre for Genomic Regulation, Barcelona, Spain

    Oscar Lao

  2. Barcelona Institute of Science and Technology (BIST), Barcelona, Spain

    Oscar Lao

  3. Universitat Pompeu Fabra (UPF), Barcelona, Spain

    Oscar Lao

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  1. Oscar Lao
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Correspondence to Oscar Lao.

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Lao, O. Selection still shapes our genome. Nat Hum Behav 5, 1600–1601 (2021). https://doi.org/10.1038/s41562-021-01232-3

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