Placing the Plague of Justinian in the Yersinia pestis phylogenetic context
Channel: Recording Archaeology
Date: 2017-01-31

The phylogenetic tree of the plague-causing pathogen Yersinia pestis has expanded in the last five years to include ancient draft genome sequences, which have allowed facets of the history of this disease to be explored in ways that were previously impossible. This pathogen has caused at least three human plague pandemics: the Plague of Justinian (6th-8th centuries), the Black Death (1347-1352 with waves continuing from the 14th-18th centuries) and the modern pandemic (19th-20th centuries), which have all been genetically characterized. Here we present the draft genomes obtained from two individuals who died in the first pandemic that allowed for genetic characterization of this pandemic. On the basis of maximum likelihood phylogenetic analyses, we conclude that the Y. pestis lineages that caused the Plague of Justinian and the Black Death 800 years later were independent emergences from rodents into humans. These results show that rodent species worldwide represent important reservoirs for the repeated emergence of diverse lineages of Y. pestis into human populations. In contrast, recently published Y. pestis sequences from the 18th century plague outbreak in Marseille, France do show ancestry in the strains obtained from Black Death victims, but are not represented in any sampled modern lineages. Taken in concert, the phylogenetics of ancient pandemic Y.pestis genomes reveal that the geographical spread of the disease and subsequent establishment of rodent reservoirs varied between pandemics.

Author - Klunk, Jennifer, McMaster University, Hamilton, Canada (Presenting author)
Co-author(s) - Wagner, David, Northern Arizona University, Flagstaff, United States of America
Co-author(s) - Sahl, Jason, Northern Arizona University, Flagstaff, United States of America
Co-author(s) - Golding, G. Brian, McMaster University, Hamilton, Canada
Co-author(s) - Waglechner, Nicholas, McMaster University, Hamilton, Canada
Co-author(s) - Holmes, Edward, The University of Sydney, Sydney, Australia
Co-author(s) - Poinar, Hendrik, McMaster University, Hamilton, Canada