Just try and tell me that this doesn’t sound like the opening to a horror movie: Researchers at the University of Copenhagen have successfully isolated and sequenced the RNA genetic information of a 14,300-year-old mummified wolf from the Pleistocene era.
Along with DNA, RNA is one of the most important molecules in cell biology. However, while DNA is known to survive under the right conditions for thousands of years, RNA is rapidly broken down in living tissue. That makes finding ancient RNA like this extraordinarily rare. This particular sample was discovered in the Siberian permafrost, enabling the sample to be kept in a state of permanent deep-freeze, thereby preserving all its nucleic acids.
“It’s significant because RNA is thought to be much less stable than DNA, both chemically and because of the activity of degradative enzymes in mammalian tissues,” Oliver Smith, lead author of the study, told Digital Trends. “[As a result], people in the paleogenomics field don’t really bother with trying it as it could just be a waste of material. However, my collaborators and I have had a fair amount of success in the past sequencing RNA from plant remains of around 750 years old, so we thought we’d take a risk and try something older and — not to put too fine a point on it — squidgier.”
Other studies have managed to recover, although not sequence, RNA from human soft tissues of around 5,000 years old. But this study pushes that boundary back by an additional 9,000 years. Doing this could help researchers learn more about the organism’s genome, as well as potentially to study the evolutionary trajectories of viruses in RNA genomes. (Although in this case, there were no viruses discovered.)
Any plans to try and use this mummified wolf genetic data to try and bring ancient wolves back to life like some heady blend of Jurassic Park and The Howling?
“The short answer to that is a resounding ‘no’,” Smith said, breaking the news gently. “Firstly, RNA isn’t actually that useful for cloning: a complete DNA genome is what is really needed. Second, constructing a physical complete genome from degraded material like this is damn near impossible given the current tech. We don’t know for sure how different this would be from a current wolf, although probably not very much at all given its appearance. Which would beg the question of why we’d want to do that. Even if we could clone it, which we can’t, we’d have a hard time justifying it ethically.”
A paper describing the work was recently published in the journal PLOS Biology.
