Traces of Human DNA on a 20,000-Yr-Old Deer Tooth Pendant Confirm It Belonged to a Siberian Woman

Scientists have extracted information from a particular burial object in Russia that would help them to identify its owner. The method has been a breakthrough for archaeologists because burial artifacts made out of stone, bones, or teeth from the Paleolithic Era have been difficult to find and attribute. Researchers are excited with the prospect of this technique because such objects contain important information about the lifestyle followed by early humans. Findings regarding the process have been published in Nature.

The object was located at Denisova Cave by archaeologists in 2019. The excavated artifact was identified to be an Upper Paleolithic deer-tooth pendant. It was set aside and later analyzed by researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig. The geneticists extracted DNA belonging to ancient humans and a wapiti deer. "The amount of human DNA we recovered from the pendant was extraordinary," said Elena Essel, lead author of the study who developed the method, stated Science Daily. "Almost as if we had sampled a human tooth."

The extraction method was noninvasive and protected the integrity of artifacts. The team observed the impact of several chemicals on the surface of archaeological bone and tooth pieces. Based on their findings, experts formulated a non-destructive phosphate-based DNA extraction method. "One could say we have created a washing machine for ancient artifacts within our clean laboratory," Essel shared. "By washing the artifacts at temperatures of up to 90°C, we are able to extract DNA from the wash waters, while keeping the artifacts intact."

Researchers focussed on the mitochondrial DNA and their findings indicated that most of the DNA came from a single human. Further analysis of the data implied that both the animal and human DNA dated back from 19,000 to 25,000 years ago. The method allowed them not to use the C14 dating procedure, which would have required sampling. The team also got a considerable portion of the nuclear genome from the human DNA, which helped them to identify the individual's gender. The team determined that the person was a woman based on the number of X chromosomes. The information also indicated that the woman was genetically related to Ancient North Eurasians, ancient individuals from East Siberia.

Scientists were delighted by the positive results. In the past, they applied the method on a set of artifacts collected from a French cave Quinçay from the 1970s to 1990s but did not get any results. For most of the objects even if the researchers were able to identify the DNA of animals whose remains were used to make the ornaments, they were unable to determine the human owners. This was because they were just obtaining the DNA of modern humans who had handled the artifacts over the years through their method. To avoid this issue, researchers focussed on objects freshly excavated from their burial location and hence honed in on objects from Denisova Cave. Now they are hoping to apply the method to more artifacts made of bone and teeth, to learn about their owners and historical trajectory.