Nei's decomposition of total expected heterozygosity in subdivided populations into within‐ and between‐subpopulation components, H_S and D_ST, respectively, is a classical tool in the conservation and management of genetic resources. Reviewing why this is not a decomposition into independent terms of within‐ and between‐subpopulation gene diversity, we illustrate how this approach can be misleading because it overemphasizes the within‐subpopulation component compared to Jost's nonadditive decomposition based on gene diversity indices. Using probabilistic partitioning of the total expected heterozygosity into independent within‐ and between‐subpopulation contributions, we show that the contribution of the within‐subpopulation expected heterozygosity to the total expected heterozygosity is not H_S, as suggested by Nei's decomposition, but H_S/s, with s being the number of subpopulations. Finally, we compare three possible approaches of decomposing total heterozygosity in subdivided populations (i.e., Nei's decomposition, Jost's approach, and probabilistic partitioning) with regard to independence between terms and sensitivity to unequal subpopulation sizes. For the conservation and management of genetic resources, we recommend using probabilistic partitioning and Jost's differentiation parameter rather than Nei's decomposition.

中文翻译：

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在细分人群中划分杂合性：Nei分解的一些误用和其他概率方法。

Nei将细分人群的总预期杂合性分解为亚群内部和亚群之间的H _S和D _ST分别是遗传资源保存和管理的经典工具。回顾为什么这不是分解为亚种群内部和亚种群之间基因多样性的独立术语的原因，我们说明了这种方法可能会产生误导，因为与基于基因多样性指数的Jost非加性分解相比，它过分强调了亚种群内部组分。通过将总预期杂合度概率划分为独立的亚群内和亚群间贡献，我们表明，Nei分解表明，亚群内预期杂合度对总期望杂合度的贡献不是H _S，而是H _S /小号，用小号是亚群的数量。最后，就术语之间的独立性以及对不等亚种群规模的敏感性，我们比较了三种在细分人群中分解总杂合性的可能方法（即Nei分解，Jost方法和概率分区）。为了保护和管理遗传资源，我们建议使用概率划分和Jost的分化参数，而不是Nei的分解。