5,500-Year-Old DNA May Solve Syphilis Origins Mystery

A skeleton buried 5,500 years ago in the Colombian highlands just rewrote what we know about one of history's most mysterious diseases.

Researchers found a previously unknown strain of syphilis bacteria in the remains of a hunter-gatherer, making it the oldest genomic evidence of the disease ever discovered. The finding pushes back our understanding of syphilis by more than three millennia.

What makes this discovery even more remarkable is that the person showed no visible signs of the disease. The team used advanced "shotgun sequencing" technology to randomly break apart and reassemble DNA fragments from a leg bone, revealing what they named TE1-3, a subspecies that split from other syphilis strains over 13,700 years ago.

Finding ancient DNA in Colombia's eastern highlands was already a victory against the odds. Temperature plays a huge role in DNA preservation, and while genetic material can survive hundreds of thousands of years in frozen environments, tropical and temperate regions rarely preserve it this long.

The location matters for another reason too. Scientists have debated syphilis origins for centuries, with two main theories competing for acceptance. Some believe the disease was widespread across Europe, Asia and the Americas, emerging in Southwest Asia around 3000 BC. Others argue Christopher Columbus's crew brought it from the Americas to Europe in 1493.

Why This Inspires

This discovery shows how new technology can unlock answers to questions that have puzzled humanity for generations. Dr. George Taiaroa from the University of Melbourne's Doherty Institute explained that many treponemal diseases are "archaeologically invisible," meaning they leave no physical trace on bones.

The ability to find pathogens even when no visible disease exists opens doors for future discoveries. Associate Professor Bastien Llamas noted that finding well-preserved microbial genomes in this part of the world is "highly unusual," making each discovery precious.

For researchers studying modern syphilis, including those tracking cases in Australia, this ancient reference point provides what Dr. Mona Taouk calls "a rare calibration point." It helps anchor when major evolutionary events occurred and improves confidence in evolutionary estimates.

The international team, led by Davide Bozzi from Switzerland's University of Lausanne, published their findings in the peer-reviewed journal Science. Their work opens new questions about the timing, routes and drivers of how the disease spread across human populations.

This 5,500-year-old skeleton is teaching us that some of history's biggest mysteries are still waiting to be solved, one DNA fragment at a time.