DNA recovered from Neanderthal teeth found in Stajnia Cave in southern Poland shows the oldest known group of Neanderthals ever found in Central Europe, according to a new study.

The study, published in Current Biology in May, analyzed DNA taken from eight of the nine teeth discovered at the site, finding that at least seven different Neanderthals had lived at the site at one time.

Using molecular branch shortening, a technique that calculates age based on the rate at which DNA mutations accumulate over time, researchers were able to place all seven individuals as living roughly within Marine Isotope Stage 5 (MIS), approximately 130,000 to 71,000 years ago. 

Radiocarbon dating was not used as the teeth are from over 100,000 years ago, the study explained.

Notably, three of the teeth - two belonging to children and one to an adult - taken from different sediment layers within the cave, all shared identical mitochondrial DNA. Meaning that they all either belonged to the same individual or that their owners shared a common female ancestor.

According to the study, finding identical DNA in teeth from different sediment layers shows that the dirt in the cave was extensively disturbed over the years.

"This is an extraordinary result because, for the first time, we are able to observe a small group of at least seven Neanderthals from Central-Eastern Europe who lived around 100,000 years ago," said Andrea Picin, professor at the University of Bologna and coordinator of the research.

"In most cases, Neanderthal genetic data come from single fossils or from remains scattered across different sites and periods. At Stajnia, by contrast, it has been possible to reconstruct a small group of individuals, providing for the first time a coherent genetic picture of Neanderthals in this part of Europe."

The DNA identified from the teeth at the Stajnia cave is not unique to Poland, the study explained, but is related to genetic material found in Neanderthal from southeastern France, the Iberian Peninsula, and the Caucasus region. 

Additionally, the study noted that the findings from Stajnia Cave contradict those of a 2024 study on a Neanderthal known as "Thorin," who was discovered at Mandrin Cave in southern France.

Researchers found that Thorin’s mitochondrial DNA places him on the same branch of the Neanderthal family tree as that of individuals whose teeth were found in the Polish cave, which, using molecular dating, would mean he lived around 100,000 years ago.

The 2024 study, however, used radiocarbon dating and estimated Thorin’s age at approximately 42,000 to 50,000 years ago.

"Our study is a reminder that the oldest chronologies must be treated with great caution," explained Sahra Talamo, professor at the University of Bologna and co-coordinator of the study. "When radiocarbon values approach the limit of calibration, it is essential not to assign more precision than the data can actually support.”

“In such cases, the comparison between archaeology, radiocarbon dating, and genetics becomes crucial."