(p. C3) What about the controversial claim that the virus may have originated in a laboratory? Both Ralph Baric’s team at the University of North Carolina at Chapel Hill and Shi Zhengli’s team at the Wuhan Institute of Virology have been working on SARS-like coronaviruses and testing their ability to infect human cells. They have for some years reported successful experiments in which they created new strains of the virus by manipulating the spike proteins that are now the focus of discovering the origin of SARS-CoV-2, and their research has included inserting furin cleavage sites.
The two teams made these so-called chimeric viruses in order to understand what makes viruses more or less dangerous and in the hope of being ready to protect people against a future SARS epidemic. In 2015 they published a joint experiment in which they combined parts of one mouse-adapted SARS-like coronavirus with a spike gene from a SARS-like coronavirus derived from Chinese bats.
In reporting their results, they expressed caution about continuing such risky experiments: “On the basis of these findings, scientific review panels may deem similar studies building chimeric viruses based on circulating strains too risky to pursue, as increased pathogenicity in mammalian models cannot be excluded.” They added: “The potential to prepare for and mitigate future outbreaks must be weighed against the risk of creating more dangerous pathogens.”
Nikolai Petrovsky and colleagues at Flinders University in Australia have found that SARS-CoV-2 has a higher affinity for human receptors than for any other animal species they tested, including pangolins and horseshoe bats. He suggests that this could have happened if the virus was being cultured in human cells, adding that “We can’t exclude the possibility that this came from a laboratory experiment.”
For the full commentary, see:
(Note: I corrected a misspelling of Petrovsky’s name.)
(Note: the online version of the commentary was the date May 29, 2020 and has the same title as the print version.)
The manuscript co-authored by Petrovsky, and mentioned above, is reported in:
Sakshi Piplani, Puneet Kumar Singh, David A. Winkler, Nikolai Petrovsky. “In Silico Comparison of Spike Protein-Ace2 Binding Affinities across Species; Significance for the Possible Origin of the Sars-Cov-2 Virus.” May 13, 2020.