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And crucially, researchers from the Wuhan lab were studying bat virus samples from Laos, before covid. https://www.business-standard.com/amp/article/current-af

• pcrh 3y ago
  Those viruses are slightly more related to SARSCoV2 than RaTG13, however note 1) that they were found even further away from Wuhan than was RaTG13 and 2) that they still remain too different from SARSCoV2 to be its direct ancestor. One of the things we know for sure is that that about 50 years of evolutionary changes separate RaTG13 and BANAL-52 from SARSCoV2, so they are not its direct ancestors.
  • dotandgtfo 3y ago
    >50 years of evolutionary changes separate RaTG13 and BANAL-52 from SARSCoV2 Do you have a source for this? Also, I'm no biologist, but is comparing the base rate of evolutionary changes still relevant if SARSCoV2 wasn't of natural origins? E.g. through creating chimeras or 'serial passaging' as described in this article? Wouldn't that create an environment where 50 years could pass in a way shorter timeframe?
    • pcrh 3y ago
      This is the study I alluded to: >Evolutionary origins of the SARS-CoV-2 sarbecovirus lineage responsible for the COVID- 19 pandemic >Divergence dates between SARS-CoV-2 and the bat sarbecovirus reservoir were estimated as 1948 (95% highest posterior density (HPD): 1879–1999), 1969 (95% HPD: 1930–2000) and 1982 (95% HPD: 1948–2009), indicating that the lineage giving rise to SARS-CoV-2 has been circulating unnoticed in bats for decades. https://www.nature.com/articles/s41564-020-0771-4 https://www.nature.com/articles/s41564-020-0771-4 You should also know that SARSCoV2 1) is not a chimeric virus, and 2) that the present study includes viruses linked to RaTGP13 but more distant from SARSCoV2, i.e. it includes evidence from viruses unassociated with the pandemic.
      • Vecr 3y ago
        What about Ralph Baric's method for splicing viruses? It's apparently really hard or impossible to detect, and that's plausibly something that could be used to make a chimeric coronavirus.
      • tripletao 3y ago
        > You should also know that SARSCoV2 1) is not a chimeric virus, There is no basis for this claim. Genomic evidence shows that SARS-CoV-2 is not a chimera of any two previously-known viruses. No possible genomic evidence could exclude a chimera of two previously-unknown viruses, and the WIV was the world's leading collector of such novel sarbecoviruses from nature. They proposed to make chimeras of them in DEFUSE. That proposal wasn't funded, but this article now reports explicit claims they did such work: > They said the Wuhan scientists had inserted furin cleavage sites into viruses in 2019 in exactly the way proposed in Daszak’s failed funding application to Darpa. You're basically rehashing Andersen's "Proximal Origins" here, and even he has moved on to more sophisticated (though still unconvincing) arguments like Pekar. As David Relman wrote almost three years ago: > This argument [that SARS-CoV-2 must be natural since it doesn't use a known backbone] fails to acknowledge the possibility that two or more as yet undisclosed ancestors (i.e., more proximal ancestors than RaTG13 and RmYN02) had already been discovered and were being studied in a laboratory—for example, one with the SARS-CoV-2 backbone and spike protein receptor-binding domain, and the other with the SARS-CoV-2 polybasic furin cleavage site. It would have been a logical next step to wonder about the properties of a recombinant virus and then create it in the laboratory. https://www.pnas.org/doi/10.1073/pnas.2021133117 https://www.pnas.org/doi/10.1073/pnas.2021133117
        • pcrh 3y ago
          We know SARSCoV2 is not a chimeric virus because similar viruses have been identified from other locations, and the pattern-matching (sequence alignment) shows that SARSCoV2 does not have any insertions or deletions that have a different evolutionary origin compared to its close relatives.
          • tripletao 3y ago
  • zosima 3y ago
    There may have been brought even closer relatives of covid-19 to Wuhan by lab personnel. We don't know as for unknown reasons the database of specimens collected by the Wuhan lab was taken down in September 2019. The distance in years between two viral strains you mention makes no sense at all, as the mutation rate is extremely dependent on environment.
  • epups 3y ago
    I don't understand this line of argument. The facts are that 1) the virus outbreak was in Wuhan, 2) that there ws a local lab working on virus samples that come from all over the world and 3) as far as we know, the particular strain that affected Wuhan is not local. Altogether, this should add confidence to the lab leak theory, not detract from it.
    • th0ma5 3y ago
      [flagged]
      • epups 3y ago
        Ok but in that scenario, a natural emergence would have come from a strain from Wuhan, while the lab leak theory explains why a virus from relatively far away had an outbreak in Wuhan.
        • th0ma5 3y ago
          Not really! Why do you need that to be true?
      • mensetmanusman 3y ago
        A particular city center?
    • Biorealism 3y ago
      The nearest relatives to SARS-CoV-2 are found in Yunnan and Laos. Both areas WIV sampled prior to the pandemic and they haven't shared their records with WHO or the NIH.
  • denton-scratch 3y ago
    The distance from Wuhan of the discovery site of RaTG13 is irrelevant, if (as the article implies) a senior team at the Wuhan lab were working on RaTG13. The article is not suggesting that Covid19 evolved from RaTG13; it is suggesting that Covid19 is a chimaera made with RaTG13.
    • th0ma5 3y ago
      [flagged]
      • denton-scratch 3y ago
        The NYT is a reputable organ, known for checking it's sources. Unlike Wikipedia, newspapers don't generally cite their sources; but if a reliable source states something like that as fact, they've probably checked. You're right: they haven't said they can prove it. [Of course, it could be propaganda, government or otherwise; or it could be a damned lie concocted by the reporter or editor. They've said they have sources, they haven't named them, so it's not unreasonable to suppose they have sources that don't want to be named.]
        • dboreham 3y ago
          Governments have a known history of both lying and deluding themselves into believing lies.
        • th0ma5 3y ago
          What does the NYT have to do with this?
  • Biorealism 3y ago
    Yes, the article suggests they had a closer precursor. The nearest relatives to SARS-CoV-2 are found in Yunnan and Laos. They are both areas WIV sampled in studying the spillover risk of SARS-related coronaviruses. They haven't shared their records with WHO or the NIH.