This Perspective article offers a meditation on FST and other quantities developed by Sewall Wright to describe population structure, defined as any departure from reproduction through random union of gametes. Concepts related to the F-statistics draw from studies of the partitioning of variation, identity coefficients, and diversity measures. Relationships between the first two approaches have recently been clarified and unified. This essay addresses the third pillar of the discussion: Nei’s GST and related measures. A hierarchy of probabilities of identity-by-state (IBS) provides a description of the relationships among levels of a structured population with respect to genetic diversity. Explicit expressions for the IBS probabilities are determined for models of structured populations undergoing regular inbreeding and recurrent mutation. Levels of genetic diversity within and between subpopulations reflect mutation as well as migration. Accordingly, indices of population structure are inherently locus-specific, contrary to the intentions of Wright. Some implications of this locus-specificity are explored.

中文翻译：

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赖特的分层 F 统计量

这篇《观点》文章对 FST 和 Sewall Wright 开发的其他数量进行了思考，用于描述种群结构，定义为通过配子的随机结合而偏离繁殖的任何情况。与 F 统计量相关的概念源自对变异划分、同一性系数和多样性度量的研究。前两种方法之间的关系最近已得到澄清和统一。本文讨论了讨论的第三个支柱：Nei 的商品及服务税及相关措施。状态身份概率层次结构 (IBS) 描述了结构化群体的遗传多样性水平之间的关系。 IBS 概率的显式表达式是针对经历定期近交和经常突变的结构化群体模型确定的。亚群内部和亚群之间的遗传多样性水平反映了突变和迁移。因此，人口结构指数本质上是特定于地点的，这与赖特的意图相反。探讨了这种位点特异性的一些含义。