An investigation of the evolutionary history of tuberculosis using ancient DNA

结核病（TB）是由结核分枝杆菌及其近亲引起的重新出现的传染病，并且如历史数据和骨骼遗骸中的病变所示，它具有影响人类的悠久历史。最近的分子证据表明M.结核病比以前认为的要古老得多，在旧世界延续了300多万年，起源于非洲。该项目的目标是分析来自骨骼样本的古代DNA，这些骨骼样本可以追溯到“探索时代”之前，期间和之后，这些骨骼样本显示了结核性骨病变的证据，并将这些数据与现代结核菌株的数据相结合，以评估结核病的进化历史及其对人类历史的影响。研究人员将从大约275个骨骼样本中提取DNA，测试它们是否存在人类和结核病DNA，然后对结核病DNA进行测序。所产生的数据将用于检查在欧洲接触之前和之后美洲结核菌株之间的关系，因为假设欧洲菌株取代了接触之前在美洲发现的菌株。此外，研究人员将评估亚洲（古代和现代）结核菌株与欧洲接触前美洲存在的菌株之间的关系，并评估17世纪和18世纪欧洲结核病患病率的增加是否是由于新菌株的传播。初步数据表明，大约17%的样本含有结核病DNA，并且在欧洲接触之前存在于美洲的菌株与今天存在的菌株不同。这项研究将有助于了解人类迁移事件和M致病性的可能变化。长期以来，结核病的流行促进了结核病的传播。

Tuberculosis (TB) is a re-emerging infectious disease caused by the bacterium Mycobacterium tuberculosis and its close relatives, and it has a long history of affecting humans as shown by both historical data and lesions in skeletal remains. Recent molecular evidence indicates that M. tuberculosis is much older than previously thought, extending over three million years in the Old World and originating in Africa. The goal of this project is to analyze ancient DNA from skeletal samples dating before, during, and after the "Age of Exploration" that show evidence of tubercular bone lesions and integrate these data with data from modern strains of tuberculosis to assess the evolutionary history of tuberculosis and its effects on human history. The researchers will extract DNA from approximately 275 bone samples, test them for the presence of human and tuberculosis DNA, and then sequence the TB DNA. The data generated will be used to examine the relationship between TB strains in the Americas before and after European contact since it is hypothesized that European strains replaced those found in the Americas prior to contact. In addition, the investigators will assess the relationship between Asian (ancient and modern) TB strains and the strains present in the Americas prior to European contact, as well as assess whether the increase in prevalence of tuberculosis during the 17th and 18th centuries in Europe was due to the spread of new strains. Preliminary data indicate that about 17% of the samples contain TB DNA, and that the strains present in the Americas before European contact were different from the strains present today. This research will aid in the understanding of how human migration events and possible changes in the pathogenicity of M. tuberculosis over time have facilitated the spread of tuberculosis.