Using shotgun DNA sequencing, researchers from the University of Zürich and elsewhere characterized the oral microbiome of skeletons uncovered in a medieval German cemetery with evidence of periodontal disease, as they report in Nature Genetics this week.
"One thing that is clear about the population we studied is that they didn't brush their teeth very often, if at all," Zürich's Christina Warinner tells LiveScience.
The researchers found that the oral microbiome of these 1,000-year-old or so Europeans is marked by disease-related bacteria. For instance, they found traces of both DNA and proteins from Tannerella forsythia, Porphyromonas gingivalis, and Treponema denticola, all known to be periodontal pathogens, in their samples.
They also uncovered DNA from food sources, allowing them to reconstruct part of the diet of the medieval Germans based on the bits of DNA they found from other organisms. For instance, they matched some of the DNA they uncovered to pigs, crucifers, and wheat.
"Amazingly, it's much the same thing you would find at a German restaurant today," Warinner tells LiveScience.