近日，英国剑桥大学教授Richard Durbin及其团队报道了一个结构化的聚结模型揭示了所有现代人类共有的深层祖先结构。2025年3月18日，国际知名学术期刊《自然—遗传学》发表了这一成果。

本文引入了一个基于聚并的隐马尔可夫模型眼镜蛇，该模型明确地表示了祖先种群的分裂和重新连接，并展示了其在多物种的模拟和真实数据上的应用。利用眼镜蛇，该研究组提供了所有现代人类历史上一段较长时期结构的证据，在这段时间里，大约150万年前分化的两个祖先群体在大约300万年前的一次混合事件中以80:20%的比例融合在一起。在他们分化之后，该研究组发现在主要祖先群体中出现了一个强大的瓶颈。研究小组推断了来自每个祖先群体的现代基因组区域，发现来自少数群体的材料与编码序列的距离密切相关，这表明它在大多数背景下是有害的。

此外，该研究团队发现大多数祖先的地区与人类尼安德特人或人类丹尼索瓦人的差异有很强的相关性，这表明大多数人口也是这些古人类的祖先。

研究人员表示，了解导致现代人类的混合事件和人口规模变化的历史是人类进化遗传学的核心。

附：英文原文

Title: A structured coalescent model reveals deep ancestral structure shared by all modern humans

Author: Cousins, Trevor, Scally, Aylwyn, Durbin, Richard

Issue&Volume: 2025-03-18

Abstract: Understanding the history of admixture events and population size changes leading to modern humans is central to human evolutionary genetics. Here we introduce a coalescence-based hidden Markov model, cobraa, that explicitly represents an ancestral population split and rejoin, and demonstrate its application on simulated and real data across multiple species. Using cobraa, we present evidence for an extended period of structure in the history of all modern humans, in which two ancestral populations that diverged ~1.5 million years ago came together in an admixture event ~300 thousand years ago, in a ratio of ~80:20%. Immediately after their divergence, we detect a strong bottleneck in the major ancestral population. We inferred regions of the present-day genome derived from each ancestral population, finding that material from the minority correlates strongly with distance to coding sequence, suggesting it was deleterious against the majority background. Moreover, we found a strong correlation between regions of majority ancestry and human–Neanderthal or human–Denisovan divergence, suggesting the majority population was also ancestral to those archaic humans.

DOI: 10.1038/s41588-025-02117-1

Source: https://www.nature.com/articles/s41588-025-02117-1