Ancient Colombian Skeleton Reveals Oldest Evidence of Syphilis in the Americas

A 5,500-year-traditional skeleton discovered in Colombia has yielded the oldest known genome of Treponema pallidum, the bacterium responsible for syphilis and related diseases. This discovery pushes back the known history of these infections in the Americas by over 3,000 years and reveals a previously unknown lineage of the pathogen.

Unearthing Ancient DNA

The remains, belonging to a middle-aged hunter-gatherer found in a rock shelter in the Sabana de Bogotá region of Colombia, were initially studied for insights into ancient human populations. Researchers from the University of California, Santa Cruz, and the University of Lausanne extracted DNA from the tibia (shin bone) – an unusual choice for pathogen research – and unexpectedly detected traces of Treponema pallidum during deep sequencing [1]. The dataset contained approximately 1.5 billion DNA fragments, allowing for the recovery of a bacterial genome without targeted enrichment.

A Unique Lineage

Genomic analysis revealed that the ancient strain of Treponema pallidum differs from all known modern subspecies. Statistical modeling indicates that this lineage diverged from other known lineages around 13,700 years ago [1]. Modern subspecies associated with syphilis, yaws, and bejel are believed to have diverged around 6,000 years ago, leaving a significant gap in the evolutionary history of these pathogens.

No Visible Signs of Disease

Interestingly, the skeleton showed no visible lesions typically associated with treponemal diseases. Researchers suggest this could be due to the ancient strain causing a form of the infection with symptoms localized to the skin, such as pinta, which is endemic to Central and South America [1], [2]. Not all infections depart detectable marks on bones, particularly in the early stages.

Implications for Understanding Disease Evolution

This discovery highlights the potential of paleogenomics – the study of ancient DNA – to contribute to our understanding of pathogen evolution. The ancient genome carries virulence factors, suggesting the lineage was capable of causing disease [1]. Further research, including the analysis of additional ancient genomes and samples from both humans and animals, is needed to determine the extent to which this lineage spread and how it relates to modern strains.

Ethical Considerations and Community Engagement

The research team emphasized the importance of ethical considerations, sharing their findings with local communities in Colombia and incorporating their input into the discussion of disease and ancestry [1]. Permits were obtained for the export and analysis of human remains, and the project treated the bones as shared heritage.

Modern Relevance

Syphilis remains a public health concern today, even though it is curable with antibiotics. Early diagnosis and treatment are crucial to prevent serious complications, especially during pregnancy [2]. A deeper understanding of the evolutionary history of Treponema pallidum may provide insights into changes that could affect the pathogen’s virulence or drug resistance.

Key Takeaways

• The oldest known genome of Treponema pallidum was recovered from a 5,500-year-old skeleton in Colombia.
• This discovery extends the known history of syphilis and related diseases in the Americas by over 3,000 years.
• The ancient strain represents a previously unknown lineage of the pathogen.
• The research highlights the importance of paleogenomics in understanding disease evolution.