Dental Research Reopens Debate over Cause of Plague
Submitted by Karen on Sat, 2003-09-20 08:15
New Scientist: Researchers have failed to find traces of the DNA of Yersinia pestis, the bacterium carried by rat
fleas thought to have caused the Plague, on 121 teeth from 66 skeletons from "plague pits" in
England, Denmark, and France.
The researchers, from Oxford University and Bart's Hospital and the London Hospital, have been
studying the skeletons' teeth because each tooth's enclosed contents may not disintegrate the
same way as other body tissues. Each tooth has its own blood supply, which can also mean that
high levels of plague bacteria could leave DNA traces inside the tooth.
Earlier French research, which found the Yersinia bacterium in DNA from teeth in southern
France, may have been flawed. "This can't prove that the Black Death wasn't Yersinia pestis, just
that we couldn't reproduce the results of the French team," said Dr. Michael Prentice, a medical
microbiologist from Bart's Hospital, when speaking with BBC News. "Ancient DNA is a very
difficult area -- it may be that these techniques will never be enough to provide an answer."