In an extraordinary breakthrough that pushes the boundaries of molecular paleontology, researchers at Stockholm University have succeeded in isolating and sequencing RNA molecules extracted from Ice Age woolly mammoth tissues, marking an unprecedented achievement in studying extinct life forms. These ancient RNA sequences, recovered from well-preserved specimens buried in the Siberian permafrost for nearly 40,000 years, represent the oldest RNA molecules ever sequenced, offering an entirely new window into the biology of long-extinct megafauna. This pioneering study has been detailed in the prestigious journal Cell, signifying a paradigm shift in our understanding of molecular preservation and genetic activity millions of years in the past.
The capacity to retrieve ancient RNA contradicts longstanding scientific assumptions that such molecules degrade rapidly after death, surviving only hours under normal conditions. Unlike DNA, which has been extensively studied due to its comparative stability, RNA’s transient nature has historically rendered it nearly impossible to recover from fossilized remains. The success of this project was made possible by accessing remarkably intact soft tissue from “Yuka,” a juvenile woolly mammoth whose tissues benefitted from the extreme cold and stable preservation conditions of Siberian permafrost. This preservation enabled the extraction of RNA that still retains traces of gene expression once active in the living mammoth’s cells, an insight that DNA alone could never provide.
RNA sequencing opens up an entirely new dimension: it reveals which genes were being actively transcribed at or near the moment of the animal’s death. As lead author Emilio Mármol explains, RNA provides a dynamic snapshot of cellular activity, showing the actual physiological processes ongoing in the mammoth’s body tens of thousands of years ago. This offers scientists a molecular diary of these ancient creatures’ biological responses to environmental stressors, disease, or even predation events shortly before death. The team’s data notably highlighted genes regulating essential muscle functions and metabolic adaptation to stress, pointing to a real-time cellular reaction perhaps linked to predation by cave lions, as previously hypothesized.
By applying cutting-edge molecular methods, the researchers identified over 20,000 protein-coding genes in the mammoth genome but found that only a subset exhibited active gene expression signatures in the muscle tissue studied. Beyond messenger RNA, the discovery of numerous non-coding RNA molecules, such as microRNAs, was particularly groundbreaking. These small regulatory RNAs orchestrate gene expression by modulating the stability and translation of messenger RNAs, underpinning complex gene regulatory networks. The detection of mammoth-specific microRNAs provides direct evidence of gene regulation mechanisms active in prehistoric times and opens new avenues for understanding post-transcriptional gene control in extinct species.
One of the most compelling aspects of this research was uncovering rare RNA sequence variants unique to mammoths, offering definitive proof that the RNA originated from the extinct species and not from modern contamination. Moreover, the team identified novel genes expressed exclusively based on RNA evidence—genes that conventional DNA sequencing would have missed—demonstrating the unprecedented power of RNA sequencing to reveal previously hidden genomic elements. This milestone showcases the synergy between ancient biomolecular preservation and modern genomic technologies, broadening the scope of paleogenomic research.
The implications of this work extend far beyond mammoths. The confirmation that RNA can survive and be sequenced after tens of thousands of years suggests new prospects for studying the gene expression profiles of a wide range of extinct organisms. Furthermore, this capability could revolutionize ancient pathogen research by enabling the recovery of RNA viruses that once infected Ice Age animals, such as influenza or coronaviruses, providing critical insights into the evolution and emergence of zoonotic diseases across deep time.
Advances in sequencing technology coupled with refined tissue preservation analyses allowed the researchers to distinguish ancient RNA molecules from background noise and contamination, ensuring the robustness and accuracy of their findings. Controlled protocols and bioinformatic analyses were pivotal, particularly in differentiating genuine ancient RNA fragments from degradation products or microbial RNA, a challenge that has complicated similar investigations in the past.
The aged RNA data gleaned from the Yuka specimen not only enriches our comprehension of the mammoth’s physiology and evolutionary biology but also sets a new standard for molecular studies of extinct life. These findings encourage revisiting other well-preserved Ice Age remains and fossils worldwide with the renewed possibility of recovering gene expression information, thus filling crucial gaps in paleobiology and evolutionary science.
Looking forward, the integration of RNA data alongside DNA, proteins, and other biomolecules heralds a multi-dimensional approach that can dissect extinct species’ biology at an unprecedented level. This holistic perspective could illuminate evolutionary adaptations, stress responses, and developmental pathways that characterized Ice Age megafauna and other extinct species. The promise of these multidimensional molecular profiles is profound, offering a more nuanced and dynamic portrayal of life as it existed in ancient epochs.
The woolly mammoth, an iconic emblem of the Pleistocene epoch, roamed vast stretches of Eurasia and North America, its evolutionary adaptations finely tuned to the severe cold and environmental challenges of the last Ice Age. Understanding its biology through ancient RNA not only enriches paleontological narratives but also may inform conservation biology and de-extinction debates by shedding light on gene regulation patterns critical for survival in subarctic climates.
This milestone discovery underscores the power of interdisciplinary collaboration among evolutionary geneticists, bioinformaticians, paleogeneticists, and molecular biologists to unravel the complex legacies preserved within ancient remains. It exemplifies how modern science leverages technological innovation to peer beyond the static genomic blueprint into the ephemeral, dynamic aspects of extinct organisms’ lives, thereby rewriting the story of life on Earth.
In conclusion, the successful sequencing of 40,000-year-old mammoth RNA redefines the limits of molecular preservation and provides an extraordinary tool for exploring life’s ancient past. The study lays a foundational framework for forthcoming research that promises to unlock the biological secrets encoded in ancient RNA, offering insights that were once inconceivable and enhancing our connection to the planet’s deep evolutionary history.
Subject of Research: Not applicable
Article Title: Ancient RNA expression profiles from the extinct woolly mammoth
News Publication Date: 14-Nov-2025
Web References: https://dx.doi.org/10.1016/j.cell.2025.10.025
References: Study published in Cell journal, DOI: 10.1016/j.cell.2025.10.025
Image Credits: Valeri Plotnikov
Keywords: ancient RNA, woolly mammoth, paleogenetics, gene expression, Siberian permafrost, Ice Age, microRNAs, molecular preservation, extinct species, evolutionary genomics, ancient viruses, paleobiology
