Researchers have uncovered ancient DNA linked to syphilis, potentially pushing back the known history of the disease by over 3,000 years. This finding was detailed in a study based on human remains that are about 5,500 years old, found in Sabana de Bogotá, Colombia, and published this month in the journal Science.
The team examined the remains and successfully identified the genome of Treponema pallidum, the bacterium responsible for syphilis and several other related diseases. Typically, these bacterial genomes are extracted from infected individuals’ teeth or bones, but in this case, they sampled the shin bone, which is somewhat atypical.
According to the researchers, this approach was surprisingly fruitful. It suggests that bones, even if they don’t display clear signs of illness, could still hold valuable pathogen DNA. The implications of this study are significant; it indicates that syphilis-related bacteria existed in the Americas long before Columbus’s arrival.
The exact origins of syphilis remain debated among scientists, but historical records show it appearing in Europe during the 15th century. The announcement claimed, “This discovery pushes the genetic record of this pathogenic species back over 3,000 years.” It’s crucial to note, however, that this study relies on a single ancient genome, and there aren’t equivalent ancient genomes available from Europe or other regions for comparison.
Future investigations will need to include multiple ancient genomes from various locations and times, along with research on human immune responses, as collaboration with indigenous communities is essential. The ongoing debate about syphilis’s origins isn’t settled just yet; this study adds an important piece to a complex puzzle.
Unexpected Findings
The discovery understandably came as a surprise since researchers weren’t actively searching for evidence of the disease. Initially, they had sequenced the DNA of the individuals to explore human history, generating an impressive 1.5 billion pieces of genetic data.
Teams from the University of California, Santa Cruz, and the University of Lausanne independently detected the bacterium T. pallidum in their screenings, leading to a collaboration to investigate further. Lars Fehren Schmitz, a geneticist involved in this research, emphasized the importance of studying ancient DNA to expand our understanding of both historical and modern health risks.
While archaeological finds related to ancient diseases are uncommon, advancements in DNA analysis techniques have led to remarkable discoveries, like the identification of a pathogen that impacted Napoleon’s soldiers during his retreat from Russia in 1812.
