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Updated: Jul 7, 2026
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
Natural selection has driven population differentiation in modern humans.
Luis B Barreiro1, Guillaume Laval, Hélène Quach
1Human Evolutionary Genetics Unit, Centre National de la Recherche Scientifique-Unité de Recherche Associée (CNRS-URA3012), Institut Pasteur, 25 rue Dr. Roux, Paris 75015, France.
Nature Genetics
|February 5, 2008
Summary
Human population diversity arises from natural selection adapting to environments. While negative selection reduces differentiation in disease genes, positive selection drives regional adaptation, influencing human traits and diseases.
Area of Science:
- Human Genetics
- Evolutionary Biology
- Population Genomics
Background:
- Phenotypic variation across human populations suggests adaptation to diverse environments.
- Previous genome-wide studies identified regions under selection, but the impact on population differentiation remains unclear.
Purpose of the Study:
- To analyze population differentiation across millions of single-nucleotide polymorphisms (SNPs).
- To elucidate how natural selection has shaped human population differentiation and adaptation.
Main Methods:
- Analysis of 2.8 million Phase II HapMap single-nucleotide polymorphisms (SNPs).
- Quantification of population differentiation across the human genome.
Main Results:
- Negative selection globally decreased population differentiation, especially in genes affecting amino acids and diseases.
- Positive selection increased differentiation in specific gene regions, driving regional adaptation via nonsynonymous and 5'-UTR variants.
Conclusions:
- Natural selection plays a dual role in human genetic diversity: reducing differentiation in essential genes and promoting it in adaptive regions.
- Identified genetic loci likely contribute to human morphological and disease-related phenotypic diversity.
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