The ‘red complex’ is an aggregate of three oral bacteria (Tannerella forsythia, Porphyromonas gingivalis and Treponema denticola) responsible for severe clinical manifestation of periodontal disease. Here, we report the first direct evidence of ancient T.forsythia DNA in dentin and dental calculus samples from archaeological skeletal remains that span from the Pre-Hispanic to the Colonial period in Mexico. We recovered twelve partial ancient T. forsythia genomes and observed a distinct phylogenetic placement of samples, suggesting that the strains present in Pre-Hispanic individuals likely arrived with the first human migrations to the Americas and that new strains were introduced with the arrival of European and African populations in the sixteenth century. We also identified instances of the differential presence of genes between periods in the T. forsythia ancient genomes, with certain genes present in Pre-Hispanic individuals and absent in Colonial individuals, and vice versa. This study highlights the potential for studying ancient T. forsythia genomes to unveil past social interactions through analysis of disease transmission. Our results illustrate the long-standing relationship between this oral pathogen and its human host, while also unveiling key evidence to understand its evolutionary history in Pre-Hispanic and Colonial Mexico.

This article is part of the theme issue ‘Insights into health and disease from ancient biomolecules'.

“红色复合体”是三种口腔细菌（连翘坦纳氏菌、牙龈卟啉单胞菌和齿垢密螺旋体）的聚集体，导致牙周病的严重临床表现。在这里，我们报告了从墨西哥前西班牙时期到殖民时期考古骨骼遗骸的牙本质和牙结石样本中存在古代连翘DNA 的第一个直接证据。我们恢复了十二个部分古代连翘基因组，并观察到样本的独特系统发育位置，这表明前西班牙个体中存在的菌株可能是随着人类首次迁徙到美洲而到达的，而新菌株是随着欧洲人和欧洲人的到来而引入的。十六世纪的非洲人口。我们还发现了连翘古代基因组中不同时期基因差异存在的实例，某些基因存在于前西班牙裔个体中而在殖民个体中不存在，反之亦然。这项研究强调了研究古代连翘基因组通过分析疾病传播来揭示过去社会互动的潜力。我们的研究结果说明了这种口腔病原体与其人类宿主之间的长期关系，同时也揭示了了解其在前西班牙裔和墨西哥殖民时期进化历史的关键证据。

本文是主题“从古代生物分子洞察健康和疾病”的一部分。