Ancient RNA expression profiles from the extinct woolly mammoth

Ancient DNA has revolutionized the study of extinct and extant organisms that lived up to 2 million years ago, enabling the reconstruction of genomes from multiple extinct species as well as the ecosystems where they once thrived. However, current DNA sequencing techniques alone cannot directly provide insights into tissue identity, gene expression dynamics, or transcriptional regulation, as these are encoded in the RNA fraction. Here we report transcriptional profiles from 10 woolly mammoths dating to the Late Pleistocene. One of these, dated to be ~39,000 years-old, yielded sufficient detail to recover tissue-specific biological functions essential for skeletal muscle metabolism, representing the oldest ancient RNA sequences recorded to date. We showcase the potential to study ancient RNA molecules beyond preconceived limitations, providing an analytical framework for validating and decoding preserved transcriptomes through time. Our findings anticipate a new era of integrative palaeo-studies combining genomics, proteomics and transcriptomics.