PNAS Letter: SARS-CoV-2 furin cleavage site was not engineered

[Mary Wilson]

September 29, 2022

https://doi.org/10.1073/pnas.2211107119

Robert F. Garry
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VIEW THE ORIGINAL ARTICLE

OPINION / MAY 19, 2022

A call for an independent inquiry into the origin of the SARS-CoV-2 virus
Neil L. Harrison, Jeffrey D. Sachs
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Harrison and Sachs (1) make a serious accusation against scientists at the University of North Carolina (UNC) and the Wuhan Institute of Virology (WIV) based on an eight-amino-acid sequence similarity between the furin cleavage site (FCS) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike and one of the FCSs of human amiloride-sensitive epithelial sodium channel α subunit (ENaC) (2). Both proteins have the sequence RRARSVAS (Fig. 1A). Harrison and Sachs cite work on rat ENaC from UNC (3, 4) and suggest that the UNC and WIV coronavirologists may have mimicked human ENaC FCS to make SARS-CoV-2 more infectious for lung epithelia.

https://www.pnas.org/doi/full/10.1073/pnas.2211107119

 

[Emily]

The immediate proximal ancestor of SARS-CoV-2 did not come directly from a bat to a human, but first evolved in an intermediate host. Two related lineages of SARS-CoV-2—lineage A and lineage B—first infected humans via the wildlife trade at the Huanan Market in Wuhan (9, 10).

This is still being debated, so UNC and WIV would not have necessarily needed another animal.

For the ENaC hypothesis to be true, UNC or WIV researchers would have had to possess the direct SARS-CoV-2 progenitor isolated from another animal—not a bat.