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Updated: Aug 8, 2026
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Automatic Identification of Dendritic Branches and their Orientation
Published on: September 17, 2021
Site Frequency Spectrum in stationary branching populations
Romain Abraham1, Jean-François Delmas2, Patrick Hoscheit3
1Institut Denis Poisson, Université d'Orléans, Université de Tours, CNRS, Orléans, France.
Journal of Mathematical Biology
|August 7, 2026
Summary
This study estimates the Site Frequency Spectrum (SFS) in branching populations, revealing insights into genetic diversity and clonal subpopulations within processes that avoid extinction.
Area of Science:
- Population Genetics
- Stochastic Processes
Background:
- Branching processes are fundamental models for population dynamics.
- Understanding genetic variation within populations is crucial for evolutionary studies.
Purpose of the Study:
- To derive estimates for the Site Frequency Spectrum (SFS) in stationary branching populations.
- To analyze the genetic makeup of clonal subpopulations in relation to their most recent common ancestor.
Main Methods:
- Utilizing a quadratic branching mechanism for continuous-state branching processes.
- Applying the infinitely-many-sites assumption for genetic variation.
- Representing population genealogy using real trees with semi-infinite branches.
Main Results:
- Derived estimates for the SFS in non-extinct branching populations.
- Presented a continuum version of the SFS as a random point measure.
- Computed the density of the expected measure for the continuum SFS.
- Estimated the size of clonal subpopulations sharing the most recent common ancestor's genotype.
Conclusions:
- The study provides a theoretical framework for analyzing genetic diversity in branching populations.
- The findings offer insights into the structure of genetic variation and clonal expansion.
- This work contributes to understanding evolutionary dynamics in populations modeled by branching processes.
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