Alexandre Arthur, Abbara Alia, Fruet Cecilia, Loverdo Claude, Bitbol Anne-Florence
Institute of Bioengineering, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, CH-1015, Switzerland; SIB Swiss Institute of Bioinformatics, Lausanne, CH-1015, Switzerland.
Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), Paris, France.
J Theor Biol. 2025 Feb 21;599:112030. doi: 10.1016/j.jtbi.2024.112030. Epub 2024 Dec 19.
The Wright-Fisher model and the Moran model are both widely used in population genetics. They describe the time evolution of the frequency of an allele in a well-mixed population with fixed size. We propose a simple and tractable model which bridges the Wright-Fisher and the Moran descriptions. We assume that a fixed fraction of the population is updated at each discrete time step. In this model, we determine the fixation probability of a mutant and its average fixation and extinction times, under the diffusion approximation. We further study the associated coalescent process, which converges to Kingman's coalescent, and we calculate effective population sizes. We generalize our model, first by taking into account fluctuating updated fractions or individual lifetimes, and then by incorporating selection on the lifetime as well as on the reproductive fitness.
赖特 - 费舍尔模型和莫兰模型在群体遗传学中都被广泛使用。它们描述了在大小固定的充分混合群体中等位基因频率随时间的演变。我们提出了一个简单且易于处理的模型，该模型在赖特 - 费舍尔模型和莫兰模型的描述之间架起了桥梁。我们假设在每个离散时间步，群体中有固定比例的个体被更新。在这个模型中，我们在扩散近似下确定突变体的固定概率及其平均固定和灭绝时间。我们进一步研究相关的合并过程，该过程收敛于金曼合并过程，并计算有效群体大小。我们首先通过考虑波动的更新比例或个体寿命来推广我们的模型，然后通过纳入对寿命以及生殖适合度的选择来进一步推广。
