Metagenomic analysis of Ancient Egyptian canopic jars

Ancient Egyptian remains have been of interest for anthropological research for decades. Despite many investigations, the ritual vessels for the internal organs removed during body preparation—liver, lungs, stomach, and intestines, of Egyptian mummies are rarely used for palaeopathological or medical investigations. These artifacts, commonly referred to as canopic jars, are the perfect combination of cultural and biological material and present an untapped resource for both Egyptological and medical fields. Nevertheless, technical challenges associated with this archeological material have prevented the application of current ancient DNA techniques for both the characterization of human and pathogenic DNA. We present shotgun-sequenced metagenomic profiles and ancient DNA degradation patterns from multiple canopic jars sampled from several European museum collections and enumerate current limitations and possible solutions for the future analysis of similar material. This is the first-ever recorded evidence of ancient human DNA found in Ancient Egyptian canopic jars and the first associated metagenomic description of bacterial taxa in these funerary artifacts. Objectives In this study, our objectives were to characterize the metagenomic profile of the Ancient Egyptian funerary vessels known as canopic jars to retrieve endogenous ancient human DNA, reconstruct ancient microbial communities, and identify possible pathogens that could shed light on disease states of individuals from the past. Methods We applied ancient DNA techniques on 140 canopic jars to extract DNA and generate whole-genome sequencing libraries for the analysis of both human and bacterial DNA. The samples were obtained from museum collections in Berlin (DE), Burgdorf (DE), Leiden (NE), Manchester (UK), Munich (DE), St. Gallen (CH), Turin (IT), and Zagreb (HR). Results Here we describe the first isolated DNA from the Egyptian artifacts that hold human viscera. No previous work was ever conducted on such material, which led to the first characterization of human DNA from Ancient Egyptian canopic jars and the profiling of the complex bacterial composition of this highly degraded, challenging, organic material. However, the DNA recovered was not of enough quality to confidently characterize bacterial taxa associated with infectious diseases, nor exclusive bacterial members of the human microbiome. Discussion In summary, we present the first genomic survey of the visceral content of Ancient Egyptian funerary artifacts and demonstrate the limitations of current molecular methods to analyze canopic jars, such as the incomplete history of the objects or the presence of uncharacterized compounds that can hamper the recovery of DNA. Our work highlights the main challenges and caveats when working with such complicated archeological material – and offers sampling recommendations for similarly complex future studies, such as incrementing the amount of starting material and sampling from the less exposed parts of the jar content. This is the first-ever recorded evidence of ancient human DNA found in Ancient Egyptian canopic jars, and our results open new avenues in the study of neglected archeological artifacts

Comparison of target enrichment strategies for ancient pathogen DNA

In ancient DNA research, the degraded nature of the samples generally results in poor yields of highly fragmented DNA; targeted DNA enrichment is thus required to maximize research outcomes. The three commonly used methods ? array-based hybridization capture and in-solution capture using either RNA or DNA baits ? have different characteristics that may influence the capture efficiency, specificity and reproducibility. Here we compare their performance in enriching pathogen DNA of Mycobacterium leprae and Treponema pallidum from 11 ancient and 19 modern samples. We find that in-solution approaches are the most effective method in ancient and modern samples of both pathogens and that RNA baits usually perform better than DNA baits

Ancient Bacterial Genomes Reveal a High Diversity of Treponema pallidum Strains in Early Modern Europe

Syphilis is a globally re-emerging disease, which has marked European history with a devastating epidemic at the end of the 15th century. Together with non-venereal treponemal diseases, like bejel and yaws, which are found today in subtropical and tropical regions, it currently poses a substantial health threat worldwide. The origins and spread of treponemal diseases remain unresolved, including syphilis' potential introduction into Europe from the Americas. Here, we present the first genetic data from archaeological human remains reflecting a high diversity of Treponema pallidumin early modern Europe. Our study demonstrates that a variety of strains related to both venereal syphilis and yaws-causing T. pallidum subspecies were already present in Northern Europe in the early modern period. We also discovered a previously unknown T. pallidum lineage recovered as a sister group to yaws- and bejel-causing lineages. These findings imply a more complex pattern of geographical distribution and etiology of early treponemal epidemics than previously understood.Peer reviewe

Mycobacterium leprae diversity and population dynamics in medieval Europe from novel ancient genomes

Hansen’s disease (leprosy), widespread in medieval Europe, is today mainly prevalent in tropical and subtropical regions with around 200,000 new cases reported annually. Despite its long history and appearance in historical records, its origins and past dissemination patterns are still widely unknown. Applying ancient DNA approaches to its major causative agent, Mycobacterium leprae, can significantly improve our understanding of the disease’s complex history. Previous studies have identified a high genetic continuity of the pathogen over the last 1500 years and the existence of at least four M. leprae lineages in some parts of Europe since the Early Medieval period

Mycobacterium leprae diversity and population dynamics in medieval Europe from novel ancient genomes.

Funder: Max-Planck SocietyFunder: St John’s College, CambridgeFunder: Fondation Raoul FollereauFunder: University of Zurich’s University Research Priority Program “Evolution in Action: From Genomes to Ecosystems”Funder: the Senckenberg Centre for Human Evolution and Palaeoenvironment (S-HEP) at the University of TübingenBackgroundHansen's disease (leprosy), widespread in medieval Europe, is today mainly prevalent in tropical and subtropical regions with around 200,000 new cases reported annually. Despite its long history and appearance in historical records, its origins and past dissemination patterns are still widely unknown. Applying ancient DNA approaches to its major causative agent, Mycobacterium leprae, can significantly improve our understanding of the disease's complex history. Previous studies have identified a high genetic continuity of the pathogen over the last 1500 years and the existence of at least four M. leprae lineages in some parts of Europe since the Early Medieval period.ResultsHere, we reconstructed 19 ancient M. leprae genomes to further investigate M. leprae's genetic variation in Europe, with a dedicated focus on bacterial genomes from previously unstudied regions (Belarus, Iberia, Russia, Scotland), from multiple sites in a single region (Cambridgeshire, England), and from two Iberian leprosaria. Overall, our data confirm the existence of similar phylogeographic patterns across Europe, including high diversity in leprosaria. Further, we identified a new genotype in Belarus. By doubling the number of complete ancient M. leprae genomes, our results improve our knowledge of the past phylogeography of M. leprae and reveal a particularly high M. leprae diversity in European medieval leprosaria.ConclusionsOur findings allow us to detect similar patterns of strain diversity across Europe with branch 3 as the most common branch and the leprosaria as centers for high diversity. The higher resolution of our phylogeny tree also refined our understanding of the interspecies transfer between red squirrels and humans pointing to a late antique/early medieval transmission. Furthermore, with our new estimates on the past population diversity of M. leprae, we gained first insights into the disease's global history in relation to major historic events such as the Roman expansion or the beginning of the regular transatlantic long distance trade. In summary, our findings highlight how studying ancient M. leprae genomes worldwide improves our understanding of leprosy's global history and can contribute to current models of M. leprae's worldwide dissemination, including interspecies transmissions

Mycobacterium leprae diversity and population dynamics in medieval Europe from novel ancient genomes

Background: Hansen’s disease (leprosy), widespread in medieval Europe, is today mainly prevalent in tropical and subtropical regions with around 200,000 new cases reported annually. Despite its long history and appearance in historical records, its origins and past dissemination patterns are still widely unknown. Applying ancient DNA approaches to its major causative agent, Mycobacterium leprae, can significantly improve our understanding of the disease’s complex history. Previous studies have identified a high genetic continuity of the pathogen over the last 1500 years and the existence of at least four M. leprae lineages in some parts of Europe since the Early Medieval period. Results: Here, we reconstructed 19 ancient M. leprae genomes to further investigate M. leprae’s genetic variation in Europe, with a dedicated focus on bacterial genomes from previously unstudied regions (Belarus, Iberia, Russia, Scotland), from multiple sites in a single region (Cambridgeshire, England), and from two Iberian leprosaria. Overall, our data confirm the existence of similar phylogeographic patterns across Europe, including high diversity in leprosaria. Further, we identified a new genotype in Belarus. By doubling the number of complete ancient M. leprae genomes, our results improve our knowledge of the past phylogeography of M. leprae and reveal a particularly high M. leprae diversity in European medieval leprosaria. Conclusions: Our findings allow us to detect similar patterns of strain diversity across Europe with branch 3 as the most common branch and the leprosaria as centers for high diversity. The higher resolution of our phylogeny tree also refined our understanding of the interspecies transfer between red squirrels and humans pointing to a late antique/early medieval transmission. Furthermore, with our new estimates on the past population diversity of M. leprae, we gained first insights into the disease’s global history in relation to major historic events such as the Roman expansion or the beginning of the regular transatlantic long distance trade. In summary, our findings highlight how studying ancient M. leprae genomes worldwide improves our understanding of leprosy’s global history and can contribute to current models of M. leprae’s worldwide dissemination, including interspecies transmissions

Ancient Bacterial Genomes Reveal a High Diversity of Treponema pallidum Strains in Early Modern Europe

Syphilis is a globally re-emerging disease, which has marked European history with a devastating epidemic at the end of the 15th century. Together with non-venereal treponemal diseases, like bejel and yaws, which are found today in subtropical and tropical regions, it currently poses a substantial health threat worldwide. The origins and spread of treponemal diseases remain unresolved, including syphilis' potential introduction into Europe from the Americas. Here, we present the first genetic data from archaeological human remains reflecting a high diversity of Treponema pallidumin early modern Europe. Our study demonstrates that a variety of strains related to both venereal syphilis and yaws-causing T. pallidum subspecies were already present in Northern Europe in the early modern period. We also discovered a previously unknown T. pallidum lineage recovered as a sister group to yaws- and bejel-causing lineages. These findings imply a more complex pattern of geographical distribution and etiology of early treponemal epidemics than previously understood