美国哈佛大学David Reich和德国马克斯·普朗克进化人类学研究所Harald Ringbauer共同合作，近期取得重要工作进展。他们开发了ancIBD，一种能够准确检测人类古代DNA的血统识别片段的方法。相关研究成果2023年12月20日在线发表于《自然—遗传学》杂志上。

据介绍，两个人之间共享的长DNA片段，即所谓的血统识别（IBD），揭示了最近的系谱联系。

研究人员介绍了ancIBD，这是一种使用隐藏Markov模型和估算基因型概率来识别古代人类DNA（aDNA）中IBD片段的方法。研究人员证明，对于aDNA数据，ancIBD准确地识别了>8 cM的IBD片段，对于全基因组测序，平均深度>0.25 x，对于1240k单核苷酸多态性捕获数据，平均深度>1 x。将ancIBD应用于4248个古代欧亚个体，研究人员确定了考古群体之间的六级亲属和系谱联系。

研究人员揭示了Corded Ware和Yamnaya群体之间长期的IBD共享，这表明波罗的海-里海草原的Yamnaya牧民和各种欧洲Corded Ware群体中，与草原相关的祖先在短短几百年内共享了大量的共同祖先。

总之，这些结果表明，检测IBD片段可以对不断增长的aDNA记录产生强有力的见解，无论是在与生活故事相关的小范围内，还是在与重大文化历史事件相关的大范围内。

附：英文原文

Title: Accurate detection of identity-by-descent segments in human ancient DNA

Author: Ringbauer, Harald, Huang, Yilei, Akbari, Ali, Mallick, Swapan, Olalde, Iigo, Patterson, Nick, Reich, David

Issue&Volume: 2023-12-20

Abstract: Long DNA segments shared between two individuals, known as identity-by-descent (IBD), reveal recent genealogical connections. Here we introduce ancIBD, a method for identifying IBD segments in ancient human DNA (aDNA) using a hidden Markov model and imputed genotype probabilities. We demonstrate that ancIBD accurately identifies IBD segments >8cM for aDNA data with an average depth of >0.25× for whole-genome sequencing or >1× for 1240k single nucleotide polymorphism capture data. Applying ancIBD to 4,248 ancient Eurasian individuals, we identify relatives up to the sixth degree and genealogical connections between archaeological groups. Notably, we reveal long IBD sharing between Corded Ware and Yamnaya groups, indicating that the Yamnaya herders of the Pontic-Caspian Steppe and the Steppe-related ancestry in various European Corded Ware groups share substantial co-ancestry within only a few hundred years. These results show that detecting IBD segments can generate powerful insights into the growing aDNA record, both on a small scale relevant to life stories and on a large scale relevant to major cultural-historical events.

DOI: 10.1038/s41588-023-01582-w

Source: https://www.nature.com/articles/s41588-023-01582-w