Here`s what China`s scientists have to say about the origin of COVID-19 – WION

During a March 15, 2020 interview, beginning at the 27:40 time point, Dr Ralph Baric, noted coronavirus scientist at the University of North Carolina, said the following when asked about the animal origin of the human COVID-19 pandemic:

As far as I know they [the Chinese] have not identified the actual reservoir species. There were reports about pangolins [scaly anteaters] as being potentially being the intermediate host, but pangolins viruses are 88-90% identical to SARS-2 [COVID-19] in comparison civet and racoon dog strains of SARS coronavirus were 99.8 identical to SARS coronavirus from 2003. In other words, you are talking about a handful of mutations between civet strains, racoon dog strains and human strains in 2003. Pangolins have over 3,000 nucleotide changes - no way they are the reservoir species [for COVID-19], absolutely no chance.

Here is what Dr Baric was saying.

It was logical to conclude that the coronavirus from the human 2003 SARS outbreak could have originated in animals because the coronavirus circulating in the civet and racoon dog populations was 99.8 per cent the same as the coronavirus eventually found in humans. That would, therefore, require only a relative handful of naturally-occurring mutations to jump to humans.

In contrast, pangolin coronaviruses are only 88-90 per cent the same as COVID-19. The huge number of naturally-occurring mutations required for pangolins to act as a reservoir species and intermediate host for COVID-19 would make it practically impossible.

Despite that, an article published by scientists from Guangzhou, China on May 7, 2020 in the prestigious journal Nature directly contradicts the comments made by Dr Baric, concluding:

The isolation of a coronavirus that is highly related to SARS-CoV-2 [COVID-19] in pangolins suggests that they have the potential to act as the intermediate hosts for SARS-CoV-2 [COVID-19].

The Guangzhou scientists concede that the bat coronavirus RaTG13, which is actually BtCoV/4991, has about a 96 per centsequence identity to SARS-CoV-2 [COVID-19] at the whole-genome level and it is reasonable to assume that bats are the native host of SARS-CoV-2 [COVID-19].

Agreeing with Dr Baric, the authors admit that, although genetically similar, it is unlikely that coronaviruses usually found in pangolins are directly linked to the outbreak because of their overall substantial sequence differences from COVID-19.

The Guangzhou group states, however, that the receptor-binding domain (RBD) of a pangolin coronavirus is nearly identical to the same structure in COVID-19, having only a single amino acid difference.

The Chinese scientists claim that a pangolin coronavirus appears to have donated the RBD to COVID-19, presumably through some type of recombinant event occurring between a bat coronavirus and a pangolin coronavirus inside a pangolin host.

The close identity of COVID-19s RBD to that of pangolins has been widely reported, but the recombinant scenario suggested by the Guangzhou research team is purely speculatively for which they provide no supporting data.

Chinas own scientists may have inadvertently stumbled upon the truth. A far more likely explanation is that the pangolin RBD was inserted into a bat coronavirus by genetic engineering.

(Disclaimer: The opinions expressed above are the personal views of the author and do not reflect the views of ZMCL)

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Here`s what China`s scientists have to say about the origin of COVID-19 - WION

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