Steve Massey
In the Bieniasz study only 0.2 % of inserts were found not to be derived from the coronavirus genome itself. The SARS2 FCS insert is not derived from the SARS2 genome, so it falls into this rare category
Robert Gifford
This Bieniasz lab paper convincingly shows shows that the SARS-COV2 nuclease NSP15 can drive insertional mutagenesis. The mechanism is plausible and elegantly demonstrated. But the conclusion that the SARS-CoV-2 FCS is "an example of such an event" is not supported by the data.