Measures of divergence between populations and the effect of forces that reduce variability
Measures of divergence between populations and the effect of forces that reduce variability
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DOI：
10.1093/oxfordjournals.molbev.a025953
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发表时间：
1998-05-01
影响因子：
10.7
通讯作者：
Charlesworth, B
中科院分区：
文献类型：
--
作者：
Charlesworth, B
Wright的F-ST和相关的统计数据经常被用来衡量同一物种的种群之间相对于物种内的净遗传多样性的分歧程度。本文比较了几种与DNA序列数据有关的F-ST定义，指出在估计迁移参数时必须谨慎使用。研究还指出，F-ST受种群内多样性水平的强烈影响。在某些情况下，如紧密连锁位点上的选择等因素预计对某些位点的群体内多样性的影响比其他位点更大，位点之间的差异可能完全来自群体内多样性的差异。结果表明，几个已发表的情况下，在果蝇的高和低重组区域之间的F-ST差异可能是以这种方式造成的。为了比较受不同强度的力影响的地点或物种之间的种群间差异水平，这些力降低了当地种群内的变异性，种群间差异的绝对量度应优先于相对量度，如F-ST。
Wright's F-ST and related statistics are often used to measure the extent of divergence among populations of the same species relative to the net genetic diversity within the species. This paper compares several definitions of F-ST which are relevant to DNA sequence data, and shows that these must be used with care when estimating migration parameters. It is also pointed out that F-ST is strongly influenced by the level of within-population diversity. In situations where factors such as selection on closely linked sites are expected to have stronger effects on within population diversity at some loci than at others, differences among loci can result entirely from differences in within-population diversities. It is shown that several published cases of differences in F-ST among regions of high and low recombination in Drosophila may be caused in this way. For the purpose of comparisons of levels of between-population differences among loci or species which are subject to different intensities of forces that reduce variability within local populations, absolute measures of divergence between populations should be used in preference to relative measures such as F-ST.