The coronavirus pandemic spinning the globe is caused by a natural virus, not one made in a lab, a new study revealed. The virus’s genetic makeup divulges that SARS-CoV-2 isn’t an assortment of known viruses, as might be expected if it were human-made. And it has rare features that have only recently been identified in crusty anteaters called pangolins, evidence shows that the virus came from nature, Kristian Andersen and his colleagues report March 17 in Nature Medicine. When Andersen, an infectious disease researcher at the Scripps Research Institute in La Jolla, Calif, first heard about the coronavirus causing an outbreak in China, he speculated where the virus came from. Primarily, researchers thought the virus was being spread by repeated infections hopping from animals in a seafood market in Wuhan, China, into humans and then being passed person to person. Analysis from other researchers has since suggested that the virus probably jumped only once from an animal into a person and has been spread from human to human since about mid-November. But shortly after the virus’s genetic greasepaint was revealed in early January, rumours began sparkling up that maybe the virus was engineered in a lab and either intentionally or inadvertently released. An ill-fated coincidence powered conspiracy theorists, says Robert Garry, a virologist at Tulane University in New Orleans. The Wuhan Institute of Virology is “in very close proximity to” the seafood market, and has conducted research on viruses, including coronaviruses, found in bats that have the potential to cause disease in people. “That led people to think that, oh, it escaped and went down the sewers, or somebody walked out of their lab and went over to the market or something,” Garry says. Accidental releases of viruses, including SARS, have happened from other labs in the past. So this is not something you can just dismiss out of hand, This is not a virus somebody would have conceived of and cobblestoned together. It has too many separate features, some of which are counterintuitive, other scientists agreed. “We see absolutely no evidence that the virus has been engineered or purposely released,” says Emma Hodcroft, a molecular epidemiologist at the University of Basel in Switzerland. She was not part of Andersen’s group but is a member of a team of scientists with Nextstrain.org that is pursuing small genetic changes in the coronavirus to learn more about how it is spreading around the world. Other scientists quickly pointed out flaws in the study and the authors retracted the report, but not before it fueled the notion that the virus was engineered. Viruses, especially RNA viruses such as coronaviruses, often swap genes in nature. Finding genes related to the pangolin viruses was especially reassuring because those viruses’ genetic makeup wasn’t known until after SARS-CoV-2’s discovery, making it improbable anyone was working with them in a lab. The similarity of SARS-CoV-2 to bat and pangolin viruses is some of the best evidence that the virus is natural, Hodcroft says. “This was just another animal spillover into humans,” she says. “It’s really the simplest explanation for what we see.” Researchers still aren’t sure exactly which animal was the source.