Scientists have successfully extracted and sequenced ancient RNA from the tissues of ten woolly mammoths preserved in permafrost. One of them, 39,000 years old, is the oldest ancient RNA sequence recorded to date.
Marble-Sanchez etc.. discovered ancient RNA molecules in the tissues of the late Pleistocene woolly mammoth. Image credit: Marmol-Sanchez etc.., doi: 10.1016/j.cell.2025.10.025.
Sequencing prehistoric genes and studying how they are activated is important for understanding the biology and evolution of extinct species.
For years, scientists have been deciphering the DNA of mammoths to piece together their genomes and evolutionary history.
However, RNA, the molecule that shows which genes are active, still remains out of reach.
“Using RNA, we can provide direct evidence of which genes are 'turned on', providing a glimpse into the final moments of the life of a mammoth that walked the Earth during the last Ice Age,” said Dr Emilio Marmol, a researcher at the Globe Institute.
“This is information that cannot be obtained from DNA alone.”
For the study, Dr. Marmol and his colleagues collected permafrost-preserved tissues from ten woolly mammoths dating to the late Pleistocene and found in paleontological fields of northeastern Siberia, stretching from the Central Indigirka region to the mainland coast of Oyogos Yar and the New Siberian Islands.
“We gained access to exceptionally well-preserved mammoth tissue excavated in Siberian permafrost, which we hoped would still contain RNA molecules frozen in time,” Dr Marmol said.
“We previously pushed the limits of DNA repair over a million years,” said Professor Lav Dahlen, a researcher at Stockholm University and the Center for Paleogenetics.
“We now wanted to see if we could extend RNA sequencing further back in time than previous studies had done.”
Researchers were able to identify tissue-specific patterns of gene expression in the muscle remains of the 39,000-year-old juvenile mammoth Yuka.
Of the more than 20,000 protein-coding genes in the mammoth genome, not all were active.
The discovered RNA molecules encode proteins that perform key functions in muscle contraction and regulation of metabolism under stress.
The scientists also discovered a variety of RNA molecules that regulate gene activity in the mammoth muscle samples.
“RNAs that do not code for proteins, such as microRNAs, were some of the most interesting results we got,” said Dr. Mark Friedländer, a researcher at the Wenner-Gren Institute at Stockholm University.
“The muscle-specific microRNAs we found in mammoth tissue provide direct evidence that gene regulation occurred in real time in ancient times. This is the first time something like this has been achieved.”
The identified microRNAs also helped the authors confirm that the results actually came from mammoths.
“We found rare mutations in some microRNAs that convincingly demonstrated their giant origin,” said Dr. Bastian Fromm, a researcher at the Arctic University Museum of Norway.
“We even discovered new genes based solely on RNA data, which has never been done before in such ancient remains.”
“RNA molecules may last much longer than previously thought.”
“Our results show that RNA molecules can survive much longer than previously thought,” said Professor Dahlen.
“This means that not only will we be able to study which genes are ‘turned on’ in different extinct animals, but we will also be able to sequence RNA viruses such as influenza and coronaviruses preserved in Ice Age remains.”
results were published on November 14, 2025 in the magazine Cell.
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Emilio Marmol-Sanchez etc.. Ancient RNA expression profiles of the extinct woolly mammoth. Cellpublished online November 14, 2025; doi: 10.1016/j.cell.2025.10.025
