Response to Keller et al on Justinianic Plague

A manuscript recently posted by Keller et al. proposes that the finding of two individuals with evidence of plague infection from our study of “137 ancient human genomes from across the Eurasian steppes” does not inform about the Justinianic Plague. We are puzzled by their conclusion, as no where in our paper we claim that the Y. pestis strains we discovered were direct ancestors of the Justinianic Plague outbreak. Their criticism appears to be based on simple mis- reading, and do not contradict our findings. Rather, we emphasize that the results in another manuscript from the same group confirm and strengthen our finding of a most recent common ancestor between DA101 and the Justinianic plague strains.