In light of all the fear and ridiculous hype lately surrounding the Ebola virus, here's some news that might sound a bit ominous. Scientists with the Blood Systems Research Institute in San Francisco have resurrected two ancient viruses recently discovered frozen in a 700-year-old layer of arctic ice, according to Phys.org.
Scientists then proceeded to infect a living organism with one of the viruses in order to study it. While thawing out ancient viruses and placing them back into living hosts sounds like risky business, the scientists hope that by studying the viruses they can learn more about virus evolution, of which little is currently known.
The good news is that neither of the viruses were infectious to humans. One of the viruses was a partial of an RNA virus believed to specifically infect insects. The other was a plant-infecting virus distantly related to modern geminiviruses and gemycircularviruses, which are typically found in dragonflies, fungi and animal feces. Researchers were able to completely reconstruct the DNA from the plant virus.
The viruses were both extracted from frozen caribou dung found in the 700-year-old layer. Researchers surmise that the caribou likely ingested the viruses when eating plants, though it's also possible that insects attracted to the dung could have deposited them there as well.
Because they were able to fully restore the plant virus, the scientists infected a Nicotiana benthamiana plant — a close relative to tobacco — with it in order to study its effects. The virus successfully replicated itself, however the infected plant did not show any disease symptoms, possibly because the plant is not the ideal host for this virus.
Because viruses mutate and change so rapidly, it can be difficult to study how they are related to one another and how they evolve. Viruses are also fragile, and thus degrade quickly. It's therefore uncommon to find an intact ancient virus, further complicating the study of their evolution. Researchers hope that by finding more preserved ancient viral strands they might be able to better understand the evolution of modern viruses.
Although there is nothing to fear about these two ancient viruses, researchers did warn that as global warming speeds up and continues to melt ice, more viral particles — some of which could very well remain infectious — might be released again into the environment.
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