The discovery of the oldest RNA ever recovered from a frozen woolly mammoth has provided scientists with a glimpse into the final moments of this ancient creature’s life. The RNA was extracted from the nearly intact carcass of a young woolly mammoth named Yuka, which was found frozen in the northern Siberian permafrost by Yukaghir hunters in 2010. Radiocarbon dating placed Yuka at approximately 40,000 years old, making it a valuable source of information about life during the last ice age.
Lead author Emilio Mármol-Sánchez, a genomicist from the University of Copenhagen, described the RNA as a snapshot of Yuka’s last minutes or hours of life. Unlike DNA, RNA records which genes were active in a cell before an organism died, providing insights into how extinct animals grew, adapted to their environments, and responded to disease and stress. Extracting RNA is challenging due to its chemical instability and rapid degradation after death, but it is crucial for reconstructing the biology of ancient organisms.
The researchers compared computational tools to ensure the authenticity of the RNA sequences recovered from Yuka’s tissue. They identified hundreds of messenger RNAs and noncoding RNAs, many of which were associated with muscle contraction and energy metabolism. Additionally, ancient muscle-related microRNAs and unique mammoth-specific microRNAs were detected, shedding light on the biology of these ancient creatures. Surprisingly, the RNA sequences revealed that Yuka was male, contrary to previous assumptions of its gender.
The discovery of ancient RNA from Yuka opens up new possibilities for studying extinct organisms and their biological functions. Oliver Smith, a forensic archaeologist involved in previous RNA discoveries, highlighted the potential for studying RNA viruses preserved in permafrost. Understanding ancient viruses can provide valuable insights into the risks of reintroducing infections into modern ecosystems and help fill gaps in our knowledge of past viral threats.
Overall, the extraction of the oldest RNA from a woolly mammoth represents a significant advancement in paleogenomics and offers a unique opportunity to study extinct animals’ biology and evolution. This breakthrough underscores the importance of preserving and studying ancient genetic material to expand our understanding of the natural world.
