Allentoft et al. paper, but instead of focusing on the human DNA recovered from ancient Eurasians, it went looking for interesting stuff in the non-human DNA (the stuff that is usually thrown away).
The result: 2,800-5,000 year old Yersinia pestis from Europe to the Altai. It will be cool to look at even older remains than the Bronze Age, but this already pushes the date for plague by a couple thousand years, and implicates steppe people in its earliest spread.
Cell Volume 163, Issue 3, p571–582, 22 October 2015
Early Divergent Strains of Yersinia pestis in Eurasia 5,000 Years Ago
Simon Rasmussen18, Morten Erik Allentoft18, Kasper Nielsen, Ludovic Orlando, Martin Sikora, Karl-Göran Sjögren, Anders Gorm Pedersen, Mikkel Schubert, Alex Van Dam, Christian Moliin Outzen Kapel, Henrik Bjørn Nielsen, Søren Brunak, Pavel Avetisyan, Andrey Epimakhov, Mikhail Viktorovich Khalyapin, Artak Gnuni, Aivar Kriiska, Irena Lasak, Mait Metspalu, Vyacheslav Moiseyev, Andrei Gromov, Dalia Pokutta, Lehti Saag, Liivi Varul, Levon Yepiskoposyan, Thomas Sicheritz-Pontén, Robert A. Foley, Marta Mirazón Lahr, Rasmus Nielsen, Kristian Kristiansen, Eske Willerslev
The bacteria Yersinia pestis is the etiological agent of plague and has caused human pandemics with millions of deaths in historic times. How and when it originated remains contentious. Here, we report the oldest direct evidence of Yersinia pestis identified by ancient DNA in human teeth from Asia and Europe dating from 2,800 to 5,000 years ago. By sequencing the genomes, we find that these ancient plague strains are basal to all known Yersinia pestis. We find the origins of the Yersinia pestis lineage to be at least two times older than previous estimates. We also identify a temporal sequence of genetic changes that lead to increased virulence and the emergence of the bubonic plague. Our results show that plague infection was endemic in the human populations of Eurasia at least 3,000 years before any historical recordings of pandemics.