The rate of adaptation in asexuals.
The rate of adaptation in asexuals.
复制标题
无性动物的适应率。
DOI：
10.1093/genetics/155.2.961
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发表时间：
2000
期刊：
影响因子：
3.3
通讯作者：
Orr,HA
中科院分区：
文献类型：
--
作者：
Orr,HA
我研究的是无性恋适应的群体遗传学。我表明，在无性物种或非重组染色体区域的适应性取代率是突变率的钟形函数：在某些时候，增加突变率降低取代率。奇怪的是，使适应率最大化的突变率仅取决于针对有害突变的选择强度。特别是，当基因组突变率U等于针对有害突变的选择系数的调和平均值时，适应是最快的，其中我们假设对有利等位基因的选择比对有害等位基因的选择更温和。这个简单的结果与有利突变和有害突变之间的效应分布的形状、群体大小和克隆干扰的作用无关。在这项工作的过程中，我推导出一个近似的概率固定在一个无性基因组或nonrecombining染色体区域，其中有利的和有害的突变发生的有利突变。
I study the population genetics of adaptation in asexuals. I show that the rate of adaptive substitution in an asexual species or nonrecombining chromosome region is a bell-shaped function of the mutation rate: at some point, increasing the mutation ratedecreasesthe rate of substitution. Curiously, the mutation rate that maximizes the rate of adaptation depends solely on the strength of selection againstdeleteriousmutations. In particular, adaptation is fastest when the genomic rate of mutation,U, equals the harmonic mean of selection coefficients against deleterious mutations, where we assume that selection for favorable alleles is milder than that against deleterious ones. This simple result is independent of the shape of the distribution of effects among favorable and deleterious mutations, population size, and the action of clonal interference. In the course of this work, I derive an approximation to the probability of fixation of a favorable mutation in an asexual genome or nonrecombining chromosome region in which both favorable and deleterious mutations occur.