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Published on: July 4, 2018
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Adaptive introgression in modern human circadian rhythm genes
Christopher Kendall1,2, Amin Nooranikhojasteh3, Guilherme Debortoli4
1Neurosciences and Mental Health Department, The Hospital for Sick Children, Toronto, ON Canada.
Npj Biological Timing and Sleep
|December 8, 2025
Summary
Modern humans inherited beneficial genes from Neanderthals and Denisovans, impacting sleep patterns and immunity. This archaic introgression influences traits like chronotype and may affect disease susceptibility.
Area of Science:
- Human Evolution
- Genetics
- Anthropology
Background:
- Modern humans interbred with archaic hominins like Neanderthals and Denisovans during migrations out of Africa.
- Archaic hominin admixture introduced novel genetic material into the modern human gene pool.
Purpose of the Study:
- To investigate adaptive introgression from archaic hominins in genomic regions related to circadian rhythm, chronotype, and sleep.
- To identify specific archaic haplotypes and their potential functional impacts in modern human populations.
Main Methods:
- Analysis of 76 worldwide modern human populations from the Human Genome Diversity Project and 1000 Genomes Project.
- Identification of 265 independent segments showing evidence of adaptive introgression, with 22 under positive selection.
- Testing for latitudinal clines and identifying archaic donors for 35 core haplotypes.
Main Results:
- Detected significant adaptive introgression from archaic hominins in genes associated with circadian rhythm, chronotype, and sleep.
- Identified 22 genomic segments under positive selection, suggesting functional adaptation.
- Found that introgression impacts genes linked to affective disorders, chronotype, and respiratory diseases.
- Observed that introgressed variants are eQTLs for immunity-related genes.
Conclusions:
- Archaic introgression played a role in adapting modern humans to diverse environments, particularly concerning circadian rhythm and sleep.
- Genetic contributions from Neanderthals and Denisovans influence complex traits and disease susceptibility in contemporary populations.
- The identified variants highlight the functional significance of archaic admixture in human adaptation and immunity.
Keywords:
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