Quoted: Caitlin Pepperell of the University of Wisconsin-Madison, who was not involved in the study, questioned the mutation rate the researchers used, which was based on a recent outbreak in Hamburg. “Generally, what we find to be the most clear-cut and unambiguous estimate for rate over thousands of years is a situation where we use ancient bacterial DNA,” she said. Such an estimate came out in 2014, but since the tuberculosis isolated from ancient humans was unexpectedly of seal origin, the field is still waiting for a robust estimate, Pepperell added. “[Wirth and his colleagues] used reasonable ranges and did reasonable things, but I think to be very definitive about dating and correlating tuberculosis history with historical events will probably have to wait for the next ancient DNA study to emerge.”
Office of Strategic Communication