My latest #originsofcovid article seems to have poked the hornet's nest of the #lableak truther community. I got insults, dismissals, even dedicated parody accounts trying to discredit me, but no rebuttal or refutation of the arguments in the article. So a quick thread 1/
My latest #originsofcovid article seems to have poked the hornet's nest of the #lableak truther community. I got insults, dismissals, even dedicated parody accounts trying to discredit me, but no rebuttal or refutation of the arguments in the article. So a quick thread 1/
In the linked article, I explore the origin question through the lens of viral #recombination This phenomena of genetic exchange between parental viruses is thought to be common in certain viral families & drive their diversity, even serve as an evolutionary "fast-forward" 2/
SARS-CoV-2 has a #mosaic genome which made it look confusing, even "stiched together" at first However, as more of its viral cousins got discovered in the wild, scientists realized that they all were chimeras because of rampant viral recombination in that particular sub-genus 3/
Recombination analyses performed by many independent teams have since established that many of SARS-CoV-2 genetic "oddities" are simply explained by recombination of existing genetic elements circulating in the wild. This includes the important "spike" gene 4/
The spike gene is one of the core elements in allowing viruses to infect new hosts, including us humans. It turns out that many bat viruses can infect humans & other speciesfrom the get go, and with viral recombination, that ability can move within the virome and its progeny. 5/
The discovery of many viral cousins of SARS-CoV-2 in the wild, and their shared recombinant ancestry, allows researchers to discard naive claims about the viral genome being "stiched together" by genetic engineers in any gain-of-function setup. There is no question that a... 6/
...natural recombinant bat ancestor to SARS-CoV-2 existed at one point in time; it did not sping from a computer sequence, was not dreamt up by a mad scientist, or stitched together from seperate viral parts. There is zero uncertainty on this left, thanks to viral discovery. 7/
Now while recombination does not have the granularity to exclude "genetic tinkering" with point mutations or small insertions on an existing bat virus, many "gain-of-function" ideas can already be discarded by simple understanding that the backbone of SARS-CoV-2 is natural. 8/
What about the now infamous "Furin cleavage site"? You might hear people lament. Recombination can not exclude this element being introduced artificially. But we have many lines of evidence to exclude any design or engineer being involved in it 🔽 9/ x.com/philippmarkoli…
What about the now infamous "Furin cleavage site"? You might hear people lament. Recombination can not exclude this element being introduced artificially. But we have many lines of evidence to exclude any design or engineer being involved in it 🔽 9/ x.com/philippmarkoli…
But back to recombination for a second. Another useful way to understand the origin story through the lens of viral recombination has to do with what it can teach us about the host reservoir and #zoonotic spillover risk. 10/
SARS-CoV-2 related viruses have been found in various horseshoe bat species; and these hypersocial bats create a complex and dynamic environment that really breeds highly broad and diverse chimeric sarbecoviruses; some of them able to infect humans from the get go. 11/