Genealogy of neutral genes and spreading of selected mutations in a geographically structured population.
Genealogy of neutral genes and spreading of selected mutations in a geographically structured population.
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中性基因的谱系和地理结构人群中选定突变的传播。
DOI：
10.1093/genetics/129.2.585
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发表时间：
1991
期刊：
影响因子：
3.3
通讯作者：
Takahata,N
中科院分区：
文献类型：
--
作者：
Takahata,N
在一个具有地理结构的种群中，基因迁移、遗传漂变和自然选择之间的相互作用引起了一些有趣的进化问题，但严格的数学处理往往非常困难。因此，本文提出了几个关于岛模型中中性基因的合并过程和选择突变的固定过程的近似公式，并通过计算机模拟检验了它们的准确性。当迁移是有限的，合并（或发散）的时间采样中性基因可以描述的卷积指数函数，如在一个panmictic人口，但它主要是由迁移率和从该样本的demes的数量。这个时间可能比繁殖个体数量相同的泛系种群中的时间要长得多。对于一个选定的突变，在整个人口的传播被制定为一个出生和死亡的过程中，固定概率在一个德莫起着关键作用。由于迁移量有限，即使是有利的突变也需要大量的世代才能传播。此外，除非选择足够强大，否则这些在某些部落中暂时固定的突变可能会被来自其他部落的非突变移民再次淹没。这些结果是潜在的有用的定量测试已提出的各种假说的起源现代人类。
In a geographically structured population, the interplay among gene migration, genetic drift and natural selection raises intriguing evolutionary problems, but the rigorous mathematical treatment is often very difficult. Therefore several approximate formulas were developed concerning the coalescence process of neutral genes and the fixation process of selected mutations in an island model, and their accuracy was examined by computer simulation. When migration is limited, the coalescence (or divergence) time for sampled neutral genes can be described by the convolution of exponential functions, as in a panmictic population, but it is determined mainly by migration rate and the number of demes from which the sample is taken. This time can be much longer than that in a panmictic population with the same number of breeding individuals. For a selected mutation, the spreading over the entire population was formulated as a birth and death process, in which the fixation probability within a deme plays a key role. With limited amounts of migration, even advantageous mutations take a large number of generations to spread. Furthermore, it is likely that these mutations which are temporarily fixed in some demes may be swamped out again by non-mutant immigrants from other demes unless selection is strong enough. These results are potentially useful for testing quantitatively various hypotheses that have been proposed for the origin of modern human populations.