Soft Sweeps III: The Signature of Positive Selection from Recurrent Mutation
Author Information
Author(s): Pleuni S. Pennings, Joachim Hermisson
Primary Institution: Ludwig-Maximilians-University Munich
Hypothesis
How does adaptation from recurrent mutation affect the signature of selection in DNA polymorphism patterns?
Conclusion
Soft sweeps from recurrent mutation leave a clear signature on neutral DNA polymorphism patterns, often clearer than classical hard sweeps.
Supporting Evidence
- The study shows that soft sweeps maintain polymorphism directly at the selected locus.
- Soft sweeps lead to stronger linkage disequilibrium compared to hard sweeps.
- The mean Tajima's D value after a soft sweep is not much different from neutrality.
Takeaway
When animals adapt to their environment, they can get helpful changes in their DNA from different mutations happening more than once. This study shows that these changes can leave clear marks in the DNA that scientists can find.
Methodology
The study used analytical tools and coalescent simulations to analyze the effects of recurrent beneficial mutations on DNA polymorphism patterns.
Potential Biases
Population structure and demography could mimic the patterns of positive selection, leading to false positives in neutrality tests.
Limitations
The study assumes a panmictic population with constant size, which may not reflect real-world scenarios.
Digital Object Identifier (DOI)
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