Did SARS-Cov-2 start in a Chinese lab?

TO SUPPORT THIS CHANNEL please do not donate to me, donate to a charity I strongly support that provides health care to poor villages in exchange for a commitment to protecting forests — two birds with one stone! The pledges are monitored, and the result has been a dramatic decrease in deforestation rates and an increase in the health of the local population.
Thanks to your generous contributions, the founders are spreading the idea to other countries.
See for an explanation of their work.

You can make a donation by bank transfer here…

One poster who says he works in a lab that handles viruses says they’re typically stored at around -80 decC, not -23 degC. I can’t verify that, but either way I can confirm that they are deep frozen, and not likely to leak out of their sealed containers.


1:00 — Bolt Report, Sky News

1:09 —

1:29 —

3:37 —

4:35 Ibid.

5:17 — h

5:31 —

5:48 —

6:16 — Ibid.

6:33 — and

7:20 —

9:24 —

11:40 —

12:28 —

14:23 —

14:29 —

14:41 —

15:09 —

15:14 —

15:29 —

15:57 —

16:08 — reading Telegraph story at

16:32 — “A pneumonia outbreak associated with a new coronavirus of probable bat origin” Peng Zhou et al., Nature 2020

16:49 Guangzhou pangolins 99% paper

16:55 — Nature – did pangolins spread virus?

19:00 (approx) — “The proximal origin of SARS-CoV-2,” — Nature Medicine 2020

20:25 —

Written by potholer54

The main purpose of this channel is to explain in simple terms the conclusions of scientific research, and correct some of the unsourced crap we hear from bloggers, politicians and the media. I am a former science journalist (see the "Who I am" video) with a degree in geology.Feel free to post. The only rules are :DON'T...1) ...plagiarize2) racist abuse3) ...advertise (i.e. just post links to other videos or websites without context)4) ...disable 'replies' 5) ...edit posts after they've been commented on, 5) ...spam and troll. The purpose of the fora is to promote discussion, not have people disrupt it. So...DO...instigate discussion, debate, criticize, point out errors so that I can correct them (with a time and a verbatim quote)Please note I don't have a Twitter account. The 'Potholer54' on Twitter is not me.


    TO SUPPORT THIS CHANNEL please do not donate to me, donate to a charity I strongly support that provides health care to poor villages in exchange for a commitment to protecting forests. Details are in the video description.

  2. Honestly conspiracy theories are getting annoying now. Because now their misleading the public and preventing us from getting to fix this problem. Thanks for this fact check.

  3. Just an FYI – I'm not sure if it's a problem on my end but comments have been cut short randomly and for no apparent reason.

    As you post you may want to check again to make sure the comment you left is complete.

  4. What a piece of debunk. I already so pissed w/ Sargon from a few mth ago. This is why we need a good fact-checking and finding truth journalism. Thanks a lot potholer54. As a geology major stud too, now im so interested to go deeper w/ science journalism

  5. My undergraduate chemistry and physics professor has posted updates and trends every day since the first cases broke out in Michigan. He did post an interesting response towards people claiming that the fatalities are over inflated that I'd like to share. 

    There is uncertainty associated with any numerical measurement, and reported COVID deaths are no different. That’s why it is always good to look for independent lines of evidence. A good test of whether COVID deaths are being over- or under-counted is to ascertain whether more deaths from any cause has increased during the pandemic.

    Consider, for example, the following article published in the Lancet, which looked at excess deaths from March through the end of May. This study indicates 122,000 deaths higher than usual were recorded during this time frame (the authors compared deaths during the pandemic to deaths over a 5-year time from between 2015 and 2020). To quote: “The number of deaths due to any cause increased by approximately 122 000 from March 1 to May 30, 2020, which is 28% higher than the reported number of COVID-19 deaths.”

    Interestingly the authors suggest that their results indicate that in some cases COVID deaths are undercounted: “Official tallies of deaths due to COVID-19 underestimate the full increase in deaths associated with the pandemic in many states.”

    If anyone has information from a peer reviewed study, such as the one I cite here, that runs counter to these findings, please share it with me. I would be interested to see it.

  6. I absolutely love that you call him "some YouTuber", as identifying that lazy dipshit in any way only serves to give him attention he does not deserve. This is the guy who streamed with a couple white supremacists..I mean race realists… and floated the rumor that the Charlottesville murder was actually a heart attack that the leftists lied about for attention….

  7. I wish you didn't have to grow older like the rest of us. If I had my way you'd continue doing what you do in your professional life and your YouTube life for generation after generation. Educating all of us in that special way , only you seem to have.

  8. Almost brilliant.
    Very good work on revealing the (excuse the colloquial idiom) Chinese whispers surrounding SARS-COV2.
    Many of your sources now need the same degree of critical inspection now though, what's good for the goose and all that.

  9. Holy shit I just looked through the comments of a video where everybody was claiming this lab bs. Every single one of them. Had to come back here just to recover from the utter ignorance that they radiated.

  10. Recent research killed the 'furin cleavage site' portion of the SARS-CoV-2 lab conspiracy theory. Actually, that portion of conspiracy theory was already dead, but paranoid denialists like Bret Weinstein peddled it anyway. It's very unlikely that evidence will convince those sorts of deluded people, but the evidence should be enough for rational people.

    First, some context:

    SARS-CoV-2's genetic sequence contains a region known as a furin cleavage site. This site allows SARS-CoV-2 to infect humans cells better, yet the precise sequence for this site is absent in known virus relatives of SARS-CoV-2. This led paranoid conspiracy theorists to suggest scientists inserted the sequence into SARS-CoV-2 in a lab. Another thread already debunked this idea (folks will need to copy-and-paste the thread's link into their browser, since just clicking the link won't send them directly to the thread):

    Some new research debunks the idea further by giving an evidence-based explanation for the origin of the furin cleavage site:

    "A palindromic RNA sequence as a common breakpoint contributor to copy-choice recombination in SARS-COV-2"

    Further discussion:

    The basic idea is as follows:

    Coronaviruses copy their genetic material using an enzyme known as a polymerase. This copying involves the polymerase using the genetic strand as a template to make another strand that complements the template strand. However, the polymerase is sloppy, allowing it to switch from one genetic strand to a different strand as a template, resulting in what scientists call a copy choice error. Copy choice error allows recombination to occur between different viruses, in which the polymerase switches from strand S1 in one virus to strand S2 in a different virus, forming a new strand S3 from strands S1 and S2. The polymerase is more likely to switch strands when it encounters a genetic sequence that is the same forwards as it is backwards; this type of sequence is known as a palindrome. This strand switch occurs because a palindrome often binds to itself to form a structure known as a hairpin, and that hairpin basically pushes the polymerase off its template strand.

    What I wrote above is introductory-level genetics and virology. It's well-evidenced in numerous viruses, including coronaviruses, and was known about for years before SARS-CoV-2 was ever discovered. So conspiracy theorists cannot claim scientists recently made it up just for the sake of covering up a lab origin of SARS-CoV-2.

    So how does this apply to SARS-CoV-2? Well, SARS-CoV-2 contains a palindromic sequence around its furin cleavage cite, and that palindrome matches one in the bat coronavirus HKU9. It's ludicrously unlikely that two related coronaviruses would randomly have that matching palindrome independently of one another. The curious can go to to first link below and do a search among coronaviruses for the palindrome given in the second link. See how many hits you find that are anything other than SARS-CoV-2 and HKU9:

    This is close to a smoking gun for the origin of the furin cleavage site. So the most likely scenario is that SARS-CoV-2 developed a furin cleavage site via copy-choice-error-mediated recombination with an ancestor of the bat coronavirus HKU9, followed by subsequent mutations. HKU9 infects bats that live alongside bats infected with coronaviruses closely related to SARS-CoV-2, and coronavirus-containing feces from these bats can also mix as bats defecate onto cave floors. So it's very likely that a virus ancestor of SARS-CoV-2 came alongside a virus ancestor of HKU9, allowing the ancestor of SARS-CoV-2 to get the furin cleavage site via copy choice error and then pass that on by descent to SARS-CoV-2.

    So at this point, SARS-CoV-2 lab conspiracy theorists should just shut up about the furin cleavage site. They ought to leave the discussion of SARS-CoV-2 to competent experts who publish research that actually advances our knowledge, instead of to nutcase conspiracists who offer nothing but baseless innuendo and paranoid delusions from crackpot sources that seek to smear informed experts. Basically: they should go away, like HIV/AIDS denialists or other people who claim scientists originally made HIV in a lab.

    Further sources below for the curious:

    Example of an HKU9 sequence containing the palindrome:

    Example of a SARS-CoV-2 sequence containing the palindrome:

    Copy choice error and recombination in coronaviruses:

    "Coronaviruses: Molecular biology" { }

    "Coronavirus diversity, phylogeny and interspecies jumping"

    page 394 of: "Biological aspects of the interspecies transmission of selected coronaviruses"

    "Evidence of the recombinant origin of a bat severe acute respiratory syndrome (SARS)-like coronavirus and its implications on the direct ancestor of SARS coronavirus"

    "Evolutionary trajectory for the emergence of novel coronavirus SARS-CoV-2"

    Different bat coronaviruses existing together:

    "Coexistence of multiple coronaviruses in several bat colonies in an abandoned mineshaft"

    "A pneumonia outbreak associated with a new coronavirus of probable bat origin"

    "A novel bat coronavirus closely related to SARS-CoV-2 contains natural insertions at the S1/S2 cleavage site of the spike protein"

    Not yet peer-reviewed: "Origin and cross-species transmission of bat coronaviruses in China"

    Not yet peer-reviewed: "Coevolution of coronavirus and paramyxovirus with their bat hosts in the same geographical areas"

  11. This video is an example of what journalism should be like.
    With Govt sponsored journalism the is a problem of censorship and screcy
    With Private sponsored journalism there is a problem of clickbait, sensationalism, stupid articles, and conspiracy theories to get paid.
    So proper journalism is derived purely from responsibility and honor.

    So potholer54 i have utmost respect for you.
    For anyone who has trouble understanding the biology bits this might help :

  12. I just now saw this video. I'm now going to unsub from Laowhy86. I saw his "I found the source" video and because he lived in China for 10 years and had the super power of "Reading Mandarin" I thought he might have been onto something. If he truly can read Mandarin (As he claims) then he intentionally lied and misled his viewers. I've been subbed to him since February and he has never made a retraction to his reporting so imo he can't be trusted. He honestly has been annoying me anyway with all his gaslighting for Trump this is just the straw that broke the camel's back. Thank you @potholer!