3 ms·

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

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 6y ago
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.”

Gatsky 6y ago

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.”