If we ever find viruses on Mars or another distant planet, they may resemble the ancient viruses scientists have discovered frozen deep in a glacier in Tibet. Researchers say ice samples taken from the Tibetan Plateau ice cores contained the genetic codes for 33 viruses, including 28 previously unknown to science, USA Today reports. The Ohio State University researchers, whose study was published in the journal Microbiome, believe the viruses originated in the soil or plants, not in humans or animals. They were found in ice cores that began to freeze almost 15,000 years ago; they were removed from the Guliya ice cap at an altitude of 22,000 feet in 2015. The researchers say the methods used could help detect viruses in other extreme icy environments, including the moon and Mars.
"These are viruses that would have thrived in extreme environments," says study co-author Matthew Sullivan, per Ohio State News. "These viruses have signatures of genes that help them infect cells in cold environments—just surreal genetic signatures for how a virus is able to survive in extreme conditions." The microbiologist tells Gizmodo that the viruses the team recovered will not pose a threat. "They are "immediately ‘killed’ by the chemistry of nucleic acids extraction, so the viruses are not active," he says. Researchers warn, however, that with the melting of glaciers worldwide accelerating, more viruses could be released in an uncontrolled manner. "Such melting will not only lead to the loss of those ancient, archived microbes and viruses but also release them to the environments in the future," they wrote. (Read more viruses stories.)