Ancient Genome Uncovers Lost Treponema Strain in Colombia

Discovery of an Ancient Pathogen GenomeResearchers have managed to reconstruct the complete genetic sequence of Treponema pallidum using human skeletal material dating back approximately 5,500 years from the Sabana de Bogotá area in Colombia. This spiral bacterium is known today as the cause of mult

Discovery of an Ancient Pathogen Genome

Researchers have managed to reconstruct the complete genetic sequence of Treponema pallidum using human skeletal material dating back approximately 5,500 years from the Sabana de Bogotá area in Colombia. This spiral bacterium is known today as the cause of multiple serious infections such as syphilis. The study results appeared in the journal Science and greatly broaden scientific understanding of the timeline during which these infections have impacted human groups across the globe.

The skeletal remains came from a rock shelter close to modern Bogotá and were dated to roughly 5,500 years before the present. Identification of this early genome stretches the documented genetic record of Treponema pallidum forward by more than three millennia. The new data strengthen arguments that treponemal infections existed in the Americas well before earlier estimates had suggested.

Geneticist Lars Fehren-Schmitz from the University of California Santa Cruz noted that the results demonstrate the distinctive value of paleogenomics for exploring species evolution and possible health hazards faced by both past and current populations. His comments highlight how ancient DNA techniques can illuminate long-term patterns of disease emergence.

Understanding Treponemal Infections

Treponema pallidum exists in three closely related subspecies that each trigger distinct illnesses including syphilis yaws and bejel. A fourth condition known as pinta is linked to Treponema carateum or the carateum subspecies of Treponema pallidum. Scientists have not yet recovered a full genome from the pinta-causing organism leaving open questions about its precise evolutionary position and taxonomic status.

Although the genetic profiles of these organisms are nearly identical researchers still lack clarity on when and through what mechanisms the separate disease forms arose. Skeletal evidence sometimes displays infection indicators yet genetic data frequently reveal more intricate histories. Significant gaps persist between the information bones can supply and the details ancient DNA can confirm regarding disease development over time.

Identification of an Early Divergent Lineage

The investigation established that the recovered ancient DNA belonged to Treponema pallidum yet failed to align with any contemporary disease-causing varieties. Although related to present-day strains the ancient genome branched off at an early point in the bacterium evolutionary tree. Anna-Sapfo Malaspinas from the University of Lausanne and group leader at the SIB Swiss Institute of Bioinformatics suggested one possibility is that the team recovered an ancient version of the organism responsible for pinta which remains poorly understood but occurs in Central and South America producing skin-localized symptoms. She emphasized that confirmation is not yet available but further study is warranted.

Genetic comparisons indicate the ancient strain diverged from other Treponema pallidum lineages around 13,700 years ago while the three modern subspecies separated much later near 6,000 years ago. These estimates align with prior work and underscore the greater diversity of treponemal pathogens in earlier periods. Elizabeth Nelson a molecular anthropologist and paleopathologist at SMU explained that current genomic information including the newly presented genome does not settle debates on the geographic origins of the disease syndromes themselves but it does establish a lengthy evolutionary background of treponemal pathogens that had already begun diversifying in the Americas thousands of years earlier than previously recognized.

Challenges in Tracing Genetic Relationships

Determining the origins of treponemal diseases remains difficult because the bacteria share extremely similar genetic compositions. At the same time they transmit differently and produce varied symptoms which complicates efforts to map their evolutionary trajectories. Researcher Davide Bozzi from the University of Lausanne and SIB Swiss Institute of Bioinformatics stated that the findings extend the association of Treponema pallidum with humans by thousands of years possibly more than 10,000 years ago during the Late Pleistocene. The work builds upon sustained archaeological and genetic investigations at the Tequendama 1 location where earlier studies by archaeologist Miguel Delgado of the Universidad Nacional de La Plata and Fehren-Schmitz supplied extensive context on the skeleton.

Unexpected Detection During Large-Scale Sequencing

The pathogen was not the initial target of the project. Scientists had sequenced the individual DNA to examine ancient human population movements generating roughly 1.5 billion genetic fragments an unusually large dataset. Routine screening by teams at the University of California Santa Cruz and the University of Lausanne separately identified traces of Treponema pallidum prompting a joint investigation. Although bacterial DNA constituted only a small fraction of the total material the extensive sequencing depth permitted reconstruction of the pathogen genome without specialized enrichment methods. The diseases caused by Treponema pallidum can produce bone lesions but only under specific conditions and not in every infected person. Most prior ancient genomes of this bacterium came from teeth or bones displaying clear disease signs. In the present case the skeleton lacked visible infection evidence. Researchers sampled a tibia which is rarely used in ancient DNA work. The positive outcome indicates that even bones without obvious disease markers can retain important genetic information.

Relevance of Ancient Disease Studies for Contemporary Health

Understanding how infectious diseases originated and evolved in the past may help scientists predict future changes and prepare modern societies for emerging health challenges. Prior to publication the research group shared results with Colombian communities acknowledging the discovery connection to national medical history. They consulted local scholars students and community members through presentations and interviews while securing all necessary export and study permits. Archaeologist Miguel Delgado remarked that this engagement was vital because the findings link directly to Colombia medical and cultural heritage. Working with scholars students and both Indigenous and non-Indigenous residents ensures ethical communication and interpretation in partnership with local groups thereby building trust supporting responsible stewardship and strengthening community ownership of the knowledge.

Collaborative Research Effort

The project was co-led by Nasreen Broomandkhoshbacht now at the University of Vermont in addition to Nelson Bozzi Malaspinas Delgado and Fehren-Schmitz. The wider team comprised Kalina Kassadjikova from the University of California Santa Cruz Jane Buikstra from Arizona State University Carlos Eduardo G. Amorim from California State University Northridge Melissa Estrada Pratt from the Instituto Colombiano de Antropología e Historia in Bogotá Gilbert Greub from the University of Lausanne and Lausanne University Hospital Nicolas Rascovan from the Institut Pasteur in Paris and David Šmajs from Masaryk University in the Czech Republic. This international cooperation enabled comprehensive analysis and responsible dissemination of the findings.