Within these frozen records of ancient times, 6.7 kilometres (22,000 feet) above sea level in China, the researchers discovered that 28 of the 33 viruses they identified had never been seen before.
"These are viruses that would have thrived in extreme environments," said Ohio State University microbiologist Matthew Sullivan, with "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."

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If they can bring back 42,000 year old roundworms just imagine what humans could be crispr'd into.