You spend an awful lot of time attacking me and not very much time attacking my arguments. That's not very scientific of you. I said I had no way to know you were actually a virologist, which I didn't. It isn't really important to the discussion though, as I said. Can we talk about this like adults? Thanks.
I'm only gonna address the science in your post from here on out. I want to make it clear I never insulted you or attacked your character, I only said I had no way to know you were a virologist and only could go off of your word.
I get your hypothesis now that you have fully stated it.
And here are some questions that need answers.
Where did they get the virus? It's not anything like any coronavirus we know of before SARS-CoV-2 emerged in humans, it's 1200 away from RATG-13.
What experimental question were they trying to answer? We already know that the furin cleavage site is necessary for some aspects of pathogenicity, but not the ones canonically thought important (cell entry for SARS-1 for example, since furin doesn't actually cleave SARS-1 or MERS). Why would they test a random unrelated coronavirus' site? Why not try the SARS-CoV-1 site? Or the MERS site? Why was it a furin site in the first place? And why did they do it on the weirdly promiscuous SARS-2 ACE2 and not in a virus like RATG-13?
Re: cleavage site, I go into extreme detail about how possible it is for cleavage sites to evolve in nature here and here:
-https://www.reddit.com/r/science/comments/gk6y95/covid19_did...
-https://news.ycombinator.com/item?id=26757881
It's really not that unusual for a cleavage site to evolve in nature, and especially not when we consider that furin cleavage sites are mutagenicity islands. It absolutely could have evolved from recombination with a distantly related coronavirus that has an extremely similar site.
Also, the cleavage site isn't even that long. Short stretches of nucleotides like that, upwards of 15-30 nucleotides, can absolutely evolve over the course of 50-70 years. Happens literally all the time. In influenza it happens on much shorter time scales. I provide evidence to that effect in the above posts.
Yes I actually address the idea of using recombinatorial cloning to make SARS-CoV-2 at several points in my post.
Nothing about the furin cleavage site makes it more likely to be unnatural than it is natural?
And so far, I don't see any compelling reason to believe that anyone would take a completely undiscovered and undescribed virus out of nature, not describe it or publish on it at all, and then start inserting random furin sites into it from random other coronaviruses.
Why would they be doing that? Is it technically /possible/? Yes, but I see no reason why it is more likely than a natural emergence.