The oldest strain of Yersinia pestis — the bacteria behind the plague that caused the Black Death, which may have killed as much as half of Europe’s population in the 1300s — has been found in the remains of a 5,000-year-old hunter-gatherer. A genetic analysis publishing June 29 in the journal Cell Reports reveals that this ancient strain was likely less contagious and not as deadly as its medieval version.
“What’s most astonishing is that we can push back the appearance of Y. pestis 2,000 years farther than previously published studies suggested,” says senior author Ben Krause-Kyora, head of the aDNA Laboratory at the University of Kiel in Germany. “It seems that we are really close to the origin of the bacteria.”
The plague-carrying hunter-gatherer was a 20- to 30-year old man called “RV 2039.” He was one of two people whose skeletons were excavated in the late 1800s in a region called Rinnukalns in present-day Latvia. Soon after, the remains of both vanished until 2011, when they reappeared as part of German anthropologist Rudolph Virchow’s collection. After this re-discovery, two more burials were uncovered from the site for a total of four specimens, likely from the same group of hunter-fisher-gatherers.
Krause-Kyora and his team used samples from the teeth and bone of all four hunter-gatherers to sequence their genomes and then tested them for bacterial and viral pathogens. They
— source sciencedaily.com | Jun 29, 2021