Ancient DNA Reveals Syphilis Origins Extend Beyond 1495

New research has uncovered that the origins of syphilis date back much further than previously believed. A team of scientists, led by anthropologist Elizabeth Nelson from Southern Methodist University, has identified a 5,500-year-old genome of the bacterium Treponema pallidum in Colombia. This discovery challenges the long-held view that syphilis was introduced to Europe in 1495 during the siege of Naples by King Charles VIII.

The 1495 siege is often cited as the beginning of the first major syphilis epidemic in Europe, which ultimately claimed up to 5 million lives. For centuries, this event shaped perceptions of the disease and led to a series of cultural blame games. The French called it the Neapolitan disease, while the English referred to it as the French Pox. This narrative, however, oversimplified the complex history of Treponema pallidum and its various strains.

The Real History of Treponema Pallidum

According to Nelson, the evolutionary history of Treponema pallidum extends far deeper than the events of the late 15th century. The recent study highlights that the lineage responsible for syphilis and related diseases like bejel and yaws is several millennia older than previously documented. The research team discovered the ancient genome while studying an individual excavated from the Tequendama I rock shelter near Bogotá, Colombia. This individual, known as TE1-3, lived during the Middle Holocene, around 5,500 years ago.

The discovery, made during a broader project on population history in the Americas, was somewhat serendipitous. Researchers typically focus on bones showing clear signs of infection, but TE1-3’s skeleton revealed no visible symptoms. Despite this, the analysis of 1.5 billion genetic fragments allowed the team to identify traces of Treponema pallidum. The resulting genome showed significant differences from known strains, indicating it represents a sister lineage diverging from modern subspecies approximately 13,700 years ago.

Implications of the Findings

The research suggests that the relationship between humans and Treponema pallidum is complex and spans continents. The divergence of the bacterium likely occurred as early humans migrated from Africa. This challenges the notion that syphilis originated from a single point in time or location. The findings indicate a greater ecological and evolutionary depth to the history of the disease, as Nelson pointed out, without entirely dismissing popular narratives.

While the events in Naples in 1495 marked a significant moment in the European understanding of syphilis, it was merely one episode in a long history of interactions between humans and treponemal pathogens. The team aims to further investigate other ancient genomes from diverse populations to understand better how these pathogens evolved and spread.

The researchers acknowledge that many questions remain unanswered. For instance, the exact timeline for when Treponema pallidum evolved its method of sexual transmission is still unclear. Additionally, it is uncertain whether the outbreak in Naples was caused by a new strain imported from the Americas or a mutation of an existing lineage in Europe.

As the scientific community delves deeper into the genetic history of syphilis and its related diseases, there is hope that this research will provide valuable insights into the past. Future studies will likely explore broader ecological interactions involving humans, animals, and pathogens, deepening our understanding of how diseases have shaped human history.