Michael 英泉 Eisen
One of the things that I think people on both sides of the COVID origins debate get wrong is thinking that something being rare disqualifies it from explaining what happened. But pandemics like COVID are rare so almost definitionally something rare/unlikely caused them. We’re not asking “Is it is likely for a pandemic like COVID to have happened?” Obviously (thankfully) that answer is no. What we are asking is “Conditioned on the fact that COVID happened what caused it?” That is we’re not asking what p(event) is we’re asking p(event | COVID) and those are very different things. In this case the fact that p(event) is non-zero is highly relevant. The fact that it is small less so. The same mistake is routinely made by lab leak opponents, who argue things like “it would be unusual to use this cloning method” or “there’s no evidence that the proposed experiments were carried out” or it’s rare for viruses to escape from labs”. What we need (and may never get) is evidence of what actually happened - debates about which of the many things that could have caused is marginally more likely to have happened doesn’t move the needle. I’m not saying it’s not important to know - it definitely is - but it’s more about shaping policies in the future. For example, the **possibility** that scientists created dangerous GOF strains and that they caused a pandemic is terrifying even if it isn’t what happened and we should do everything in our power to prevent it in the future. Similarly the fact that FCSs can emerge naturally is also scary and we should think about what that means from a public health perspective. tl;dr pandemics are rare, so the events that caused them are rare
Steve Massey
In the Bieniasz study only 0.2 % of inserts were found not to be derived from the coronavirus genome itself. The SARS2 FCS insert is not derived from the SARS2 genome, so it falls into this rare category