They then analysed the DNA and identified three cases of Yersinia pestis in two children estimated to be aged between 10-12 years old when they died, and one woman aged between 35-45. Radiocarbon dating was used to show it’s likely the three people lived at roughly the same time. Using genome sequencing, the researchers showed that this strain of the Yersinia pestis looks very similar to the strain identified in Eurasia at the same time. The individuals identified all lacked the yapC and ymt genes, which are seen in later strains of plague, the latter of which is known to play an important role in plague transmission via fleas. This information has previously suggested that this strain of the plague was not transmitted via fleas, unlike later plague strains such as the one that caused the Black Death.