Researchers from the University of Copenhagen have found 5,700-year old birch pitch chewing gum. Amazingly, they have extracted a complete human genome from it! What does this tell us about our past?
Pitch is made by heating the bark of a Birch tree. It was used for multiple purposes in the stone ages, dating back to the Palaeolithic period. Uses included glue, antiseptic, and chewing gum!
How do we know this? Preserved birch pitch has been found bearing teeth marks. This indicates it was used either to relieve toothache, as toothpaste, or as chewing gum.
The discovery was made in Denmark. Excavations are being carried out as part of the building of the Fehmarn tunnel. Theis Jensen, Postdoc at Globe Institute, says that the site ‘is completely unique. Almost everything is sealed in mud, which means that the preservation of organic remains is absolutely phenomenal‘.
Jensen participated in the excavation and worked on the study as part of his PhD.
The human genome
So what can researchers tell us from this ancient chewing gum? As it happens, rather a lot!
DNA is a well-known phrase these days, but in scientific terms, it is quite new. The Human Genome Project (HGP) was completed only in 2003. A genome is the complete set of an organisms DNA. This was the first time complete genome sequencing had been mapped.
Researchers from the University of Copenhagen were able to extract a complete ancient human genome. This is the first time this has been possible from anything but human bones.
What can scientists tell us?
The ‘chewer’ was female and genetically similar to European people. This is unusual since the pitch was found in Scandinavia. Scientists have named her Lola. They believe she had dark skin, dark hair and blue eyes.
Where the science becomes valuable outside of historical purposes, is in tracing viruses. Lola’s sample included pathogens which have since been analysed. Some of the DNA may relate to the Epstein-Barr virus. This is the virus that causes glandular fever.
How is this breakthrough relevant to modern medicine?
Pathogens are the microorganisms that cause disease. Understanding how pathogens have evolved over time is crucial to being able to continue to fight the spread of dangerous illnesses.
Analysing the evolution of these pathogens shows us how they have mutated. This gives scientists indicators as to how they might further evolve and helps to predict how to fight them.
Hannes Schroeder is Associate Professor at the Globe Institute based within the University. Schroeder says that ‘it may help predict how a pathogen will behave in the future, and how it might be contained or eradicated‘.
I think it is extraordinary to have a reference point for DNA dating back this far, without any bones. That science can analyse and discover such detail puts medical research on the front foot, with more opportunities to predict how diseases might alter over time.
Another day, another scientific breakthrough!