Researchers have successfully extracted a complete human genome from a 5,700-year-old piece of chewing gum found in Denmark.
One day in the Neolithic, a person threw his chewing gum made from birch tar in a shallow lagoon on the island of Lolland. Almost 6,000 years later, when construction work begins on the Fehmarn tunnel to link Denmark to Germany, researchers find this chewy paste. They then extract the DNA inside and can reconstruct the entire genome of its former owner.
“This is the first time that we have obtained a complete ancient genome from anything other than bones or teeth,” says Hannes Schroeder, molecular anthropologist at the University of Copenhagen. The conservation of the gum is quite extraordinary. We weren’t expecting that much information. ”
A young girl with blue eyes
After analyzes, the researchers were able to determine that the person who had chewed this “chewing gum” was a hunter-gatherer of European type who had dark skin and hair and blue eyes. She lived near the lagoon about 5,600 years ago, according to the carbon dating of birch tar.
This material, obtained by heating the bark of the tree, was then often used as a natural adhesive. We used tar to make tools mainly. But this “paste” also had other applications.
In fact, juvenile teeth marks have very often been noticed. Assuming that birch bark contains antiseptic substances, the researchers suggest that these chewing gums were also used as toothbrushes by our ancestors.
Scientists have not been able to determine the age of the person here, but since the children at the time appeared to be chewing birch tar, they suspect that he was young.
The analyzes also revealed genetic material from duck and hazelnuts. Researchers suggest it was probably his last meal.
Dozens of bacteria
Several dozen bacterial species have also been isolated, three of which could possibly cause pneumonia. The researchers also spotted the Epstein-Barr virus, which can cause glandular fever. On the other hand, these microbes can be present in the oral environment but remain “asleep”. It is therefore unknown whether these illnesses actually led to the death of this young girl.
In addition to the “chewing gum”, the excavations also made it possible to find bones of cattle, deer, wild cats, dogs and otters, all dated over several generations. This information suggests that “this place was of particular importance to local communities,” said Theis Jensen, co-author of the study. These people did not live on the site, but probably on dry land a few hundred meters away. ”
