
A Proposed Origin for SARS-CoV-2 and the Covid-19 Pandemic - Gatsky
https://www.independentsciencenews.org/commentaries/a-proposed-origin-for-sars-cov-2-and-the-covid-19-pandemic/
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hanklazard
I find this hypothesis compelling, and this is such a strong write-up.

One part that I’m a bit confused about is around the origin of the furin site.
The post has a challenge in explaining it, since it’s such a large stretch of
nucleic acid. They end up explaining it with the idea that the virus actually
pulled it from human lung mRNA but isn’t there at least one other very strong
possibility?: it was inserted there intentionally in the lab.

It’s been a little while since I’ve done any actual molecular biology in the
lab but I have to believe that either direct insertion of an RNA sequence into
the viral genome or an indirect method using DNA for the manipulation with
subsequent re-insertion into the virus is possible.

I actually appreciate that the post only mentions in passing the possibility
of genetic manipulation as they’re explanation seems slightly more simple (and
certainly less accusatory), just seems like it deserves at least another
mention at the end as a logical possibility.

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Gatsky
They propose that the virus evolved the furin site during infection of the
miners. It wasn't pulled from lung mRNA, but evolved due to random
mutagenesis. This seems to me to be the weakest part of the whole story. But
they argue that this is more plausible than the same thing happening in a
pangolin.

~~~
hanklazard
I should have been more specific with my wording. They are proposing that
there was a recombination event which incorporated the human furin cleavage
site into the viral RNA. This would be lifting the sequence directly from the
human gene product, as I read it.

> It is known from plants that positive-stranded RNA viruses recombine readily
> with host mRNAs (Greene and Allison, 1994; Greene and Allison, 1996; Lommel
> and Xiong, 1991; Borja et al., 2007). The same evidence base is not
> available for positive-stranded animal RNA viruses, (though see Gorbalenya,
> 1992) but if plant viruses are a guide then acquisition of its furin site
> via recombination with the mRNA which encodes ENaC-a by SARS-CoV-2 is a
> strong possibility.

This seems like more of a stretch than direct genetic manipulation in the lab.

~~~
Gatsky
I don’t think that’s what they are saying:

“Inside the miners a large tissue was simultaneously infected by a population
of poorly-adapted viruses, with each therefore under pressure to adapt. Even
if the starting population of virus lacked any diversity, many individual
viruses would have acquired mutations independently but only recombination
would have allowed these mutations to unite in the same genome. To recombine,
viruses must be present in the same cell. In such a situation the
particularities of lung tissues become potentially important because the
existence of airways (bronchial tubes, etc.) allows partially-adapted viruses
from independent viral populations to travel to distal parts of the lung (or
even the other lung) and encounter other such partially-adapted viruses and
populations. This movement around the lungs would likely have resulted in what
amounted to a passaging effect without the need for a researcher to infect new
tissues. Indeed, in the Master’s thesis the observation is several times made
that areas of the lungs of a specific patient would appear to heal even while
other parts of the lungs would become infected.”

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bediger4000
I flagged this because it seems to be hiding its political motivations:

"The media, normally so enamoured of controversy, has largely declined even to
debate the possibility of a laboratory escape. Many news sites have simply
labelled it a conspiracy theory."

~~~
Gatsky
Criticising the media’s biased coverage of a scientific topic doesn’t seem
politically motivated to me. The statements you highlight could just be
‘true’?

