Viral: The Search for the Origin of COVID-19

They also realized that other coronaviruses in the same family as Sars-Cov-2 did not have a similar password, much less one positioned so well. That finding raised the question of why Sars-Cov-2 did. A few scientists speculated openly whether the virus had been designed or modified in a laboratory. But most dismissed those questions as irrelevant,

Genetic sequencing showed that SARS-2 is 96.2 percent identical to a coronavirus found years ago in a bat in a cave in Yunnan, China (that virus is known as RaTG13). This confirms that SARS-2 originated in bats, where it probably circulated unnoticed for decades, but the virus also might have spent some time in pangolins before coming to our own sp

But bat coronaviruses generally do not have furin cleavage sites, raising the question of how Sars-Cov-2 had acquired its own. RaTG13, the virus that the Wuhan Institute had admitted working with, was the closest known viral relative of Sars-Cov-2, but by virology standards it was still relatively distant, and it lacked the furin cleavage site.