Scientists Uncover Ancient RNA from Woolly Mammoth Yuka

Scientists have successfully isolated and sequenced the oldest-known RNA from a juvenile male woolly mammoth named Yuka, who lived approximately 39,000 years ago in Siberia. This groundbreaking discovery, announced on October 13, 2023, reveals vital insights into Ice Age biology and challenges previous assumptions about RNA preservation.

Yuka was unearthed in 2010 from the Siberian permafrost along the Oyogos Yar coast near the Laptev Sea. The analysis of Yuka’s RNA has provided a deeper understanding of the mammoth’s biological functions, revealing which genes were active at the time of death and indicating signs of cell stress. This accomplishment marks a significant advancement in the field, as most knowledge about prehistoric organisms has relied on skeletal fossils, which have limitations in revealing biological details.

Revolutionizing Our Understanding of Ancient Life

RNA, or ribonucleic acid, is essential for various biological processes, acting as a messenger that relays genetic information to cells. Emilio Mármol, a geneticist, veterinarian, and bioinformatician at the University of Copenhagen’s Globe Institute and lead author of the study published in the journal Cell, emphasized the importance of this discovery. “With RNA, you can access the actual biology of the cell or tissue happening in real time within the last moments of life of the organism,” he stated.

The researchers found that the RNA in Yuka’s tissues coded for proteins involved in muscle contraction and metabolic regulation during stress. These findings offer a unique glimpse into the functionality of woolly mammoths at a time when they roamed the Earth. The study of ancient RNA complements previous advances in the analysis of ancient DNA and proteins, providing a more comprehensive view of these long-extinct species.

Previously, the oldest RNA recovered was from a wolf cub that lived around 14,000 years ago. This new research indicates that RNA can survive far longer than previously believed, with the frigid Siberian conditions playing a crucial role in preserving Yuka’s biomolecules.

Insights into Yuka’s Life and Death

The analysis revealed that Yuka had suffered trauma before its death, evidenced by deep cuts on its hide, likely inflicted by a cave lion, an extinct relative of today’s African lion. Love Dalén, a geneticist from Stockholm University and co-author of the study, noted that while these injuries were significant, they were not severe enough to have caused Yuka’s death. “It is still a bit unclear why Yuka died,” he added.

Yuka was initially thought to be female based on earlier genetic analysis, but recent DNA sequencing confirmed the mammoth was male, standing approximately 1.6 meters (5 feet 3 inches) at the shoulder. The research team believes that under optimal conditions, RNA can potentially be recovered from even older remains, paving the way for further exploration of gene expression in Ice Age megafauna.

Mármol expressed hope that this work will inspire renewed interest in studying RNA from various ancient remains, not only from extinct species but also from medieval and historical contexts. The implications of this research extend beyond the Ice Age, offering exciting possibilities for understanding the biology of both extinct and extant organisms.

This remarkable achievement sheds light on the intricate biology of woolly mammoths and enhances our understanding of life during the Ice Age, proving that even the most fragile biomolecules can endure the test of time under the right conditions.