The findings, published in the journal Nature Communications, provide fresh insight into how oral bacteria colonize and persist in humans, with potential implications for health, disease and microbiome research.

You might think that modern medical science knows everything there is to know about the human body. But even within the last decade, small, previously unknown organs have been discovered, and there’s one area of human biology that is currently going through a research renaissance, the microbiome.

This includes familiar areas such as the gut microbiome, but also the oral microbiome.

Inspired in part by recent discoveries of extraneous DNA in the microbiome of soil, Project Research Associate Yuya Kiguchi and his team turned their sights to a large set of saliva samples collected by the Yutaka Suzuki Lab of the Graduate School of Frontier Sciences at the University of Tokyo. They wondered if they might find something similar in human saliva.