BACKGROUND The statistical distribution of the similarity or difference between pairs of paralogous genes, created by whole genome doubling, or between pairs of orthologous genes in two related species is an important source of information about genomic evolution, especially in plants. METHODS We derive the mixture of distributions of sequence similarity for duplicate gene pairs generated by repeated episodes of whole gene doubling. This involves integrating sequence divergence and gene pair loss through fractionation, using a branching process and a mutational model. We account not only for the timing of these events in terms of local modes, but also the amplitude and variance of the component distributions. This model is then extended to orthologous gene pairs. RESULTS We apply the model and inference procedures to the evolution of the Solanaceae, focusing on the genomes of economically important crops. We assess how consistent or variable fractionation rates are from species to species and over time.

中文翻译：

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基于同源分布的多倍体、物种形成和损失推断的分支过程。

背景技术通过全基因组加倍产生的旁系同源基因对之间或两个相关物种中的直系同源基因对之间的相似性或差异的统计分布是关于基因组进化的重要信息来源，尤其是在植物中。方法我们推导出由重复的全基因加倍事件产生的重复基因对的序列相似性的混合分布。这涉及使用分支过程和突变模型，通过分级整合序列分歧和基因对丢失。我们不仅根据局部模式考虑这些事件的时间，而且还考虑分量分布的幅度和方差。然后将该模型扩展到直系同源基因对。结果我们将模型和推理程序应用于茄科的进化，重点关注重要经济作物的基因组。我们评估不同物种和不同时间的分馏率的一致性或可变性。