SARS-CoV-2: The Genesis: Still Wrapped in Mystery: Yet Another Professional Comment

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Sukla Sen

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Jun 25, 2021, 4:46:34 AM6/25/21
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So, it's still pretty much uncertain whether the SARS-CoV-2 evolved "naturally" - maybe in a bat, and then jumped to humans - either directly or via an intermediate host (pangolin?), as - at least for a while rather compellingly, suggested by a research paper published in the 'Nature' (in March 2020: <https://www.nature.com/articles/s41591-020-0820-9>) or it was fabricated in a lab and then got "released" or "leaked".

It's quite possible, in fact even likely, that it'd never be known for certain - neither the evolutionary track would ever be sufficiently mapped nor the "smoking gun" substantiating lab origin come to be unearthed.
It's precisely in this context, the sage adage that absence of proof is no proof of absence would emerge all that salient.

But, the odds, at least for now, are favouring the lab origin theory.
The (reported) persistent secretiveness on the part of the Chineses authorities has also, no doubt, contributed.
(The POTUS has, in the meanwhile, asked the American intelligence community to investigate and produce a report by late August: <https://www.cnn.com/2021/05/26/politics/biden-intelligence-community-pandemic-origins-report/index.html>.
That'd, definitely, be of interest.)

<<Biologists have seen what evolution can create: the whole natural world around us. We believe that evolution can do anything. But the fact that evolution might have been able to generate SARS-CoV-2 doesn’t mean that that’s how it came about. I think we very much need to find out what was happening in the Wuhan Institute of Virology. I think that we can’t say for sure yet whether the SARS-CoV-2 virus came from natural origins or if it was genetically manipulated somehow.
...
...(W)ithin the SARS-CoV-2 genome there is an insertion of 12 nucleotides that is entirely foreign to the beta-coronavirus class of virus that SARS-CoV-2 is in. There are many other viruses in this class, including the closest relative of SARS-CoV-2 by sequence, and none of them have this sequence. The sequence is called the furin cleavage site.

To back up a little bit: In order to infect a cell, the spike protein on the surface of viruses like SARS-CoV-2 needs to first be cut, or cleaved. The cut needn’t be terribly exact, but it needs to be cut. Different viruses attract different kinds of cellular “scissors,” so to speak, to make this cut; the furin cleavage site attracts the furin protein providing the most efficient way to make a cut. You don’t need a furin cleavage site to cut the protein, but it makes the virus more efficiently infectious.

So where did it come from in SARS-CoV-2? There are other viruses that have furin cleavage sites, other coronaviruses, though not the family of beta-coronaviruses. So this sequence’s nucleotides could have hopped from some other virus. No one has identified a virus that has exactly this sequence, but it could have come from something close, then evolved into the sequence that we see today.

I’m perfectly willing to believe that happened, but I don’t think it’s the only way that that sequence could have appeared. The other way is that somebody could have put it in there. You can’t distinguish between the two origins from just looking at the sequence. So, naturally, you want to know were there people in the virology laboratory in Wuhan who were manipulating viral genetic sequences? It’s really a question of history: What happened?

When I first saw the sequence of the furin cleavage site—as I’ve said, other beta coronaviruses don’t have that site—it seemed to me a reasonable hypothesis that somebody had put it in there. Now, I don’t know if that’s true or not, but I do know that it’s a hypothesis that must be taken seriously.>>


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