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Comment by Pyramus | Hacker News Reader

"Considerable suspicion" is over-selling it in my opinion. The arguments I've heard go along the lines of 'the virus is surprisingly well adapted to humans'. This reasoning, however, is text-book survivor bias:

Given we observe a pandemic, the probability for the virus to be well adapted is very high.

What we do know is:

* There is a highest safety level virus lab in Wuhan.

* Lab escapes do and did happen.

As far as I know we simply do not have evidence if or if not gain of function research played a role.

\edit: formatting. Can somebody please explain the downvotes?

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> As far as I know we simply do not have evidence if or if not gain of function research played a role.

You can examine phylogenetic distance -- the degree of evolutionary drift that the initial virus had from others which are subject to natural (in-the-wild) evolution. COVID is way out there. And even then the closest "natural" virus had its genome published by the Wuhan lab long after the initial outbreak.

The lack of any close relatives suggests that gain-of-function very well may have taken place, as does the heightened vulnerability of typical lab-animals. What there isn't much evidence of is zoonotic transfer.

That's a reasonable argument. But it requires a very high level of understanding of (bat) corona-viruses in general with a majority of corona-viruses that exist having been sequenced etc.

From my (limited) understanding we only know about a fraction of corona-viruses out there, and hence there is great uncertainty in the phylogenetic modelling.

I haven't seen a credible write-up, if you can point me in the right direction, that would be appreciated.

RaTG13 geonome was published January 23, 2020 by Wuhan Institute of Virology.

https://www.biorxiv.org/content/10.1101/2020.01.22.914952v1....

https://www.ncbi.nlm.nih.gov/nuccore/MN996532

Actually part of the genome of RaTG13 was published as RaBtCoV/4991 back in 2016.

Some people suspected it [0] and eventually Dr. Shi confirmed it [1] after.

[0] https://www.researchgate.net/publication/341547726_Understan...

[1] https://science.sciencemag.org/content/369/6503/487.full

Thank you for the reference. [1] particularly interesting.

It might be that people are taking issue with the survivorship-bias argument.

The important question here is: Given a virus that is as well adapted to humans as SARS-CoV-2, how likely is it that it emerged spontaneously (without a trace of any intermediate states, afaik) vs. how likely is it that it leaked from a lab that has high safety standards, but was probably producing viruses just like it.

It is indeed not surprising that the virus is well adapted to humans, seeing as we are experiencing a pandemic, but that is disconnected from wondering how it got to be so.

> (without a trace of any intermediate states, afaik)

It's pretty clear that SARS-CoV-2 shares an ancestor with RaTG13 [0]. Their S-proteins, the main factor in human adaptation, are a 97.8% match, which can be explained with about a decade of divergence, putting the common ancestor somewhere in late 2000s.

Why RaTG13 (then called RaBtCoV/4991) research was shelved by China, when it's been one of the suspects of the death of 3 miners with SARS-like symptoms in 2012[1], is the concerning part of it all. The chances of it being lab made/grown/modified are just way too slim.

[0] https://www.nature.com/articles/s41594-020-0468-7

[1] https://www.sciencemag.org/news/2014/03/new-killer-virus-chi...

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