Flavinkins (@Flavinkins)

More importantly, when considering the current RGS systems, it turned out that none of the supposed ReCCA components are compatible with the cloning scheme that somehow were identical in their RE site order and REase use between U.S. and Chinese publications—the 2 BsaI sites within the ORF1a strongly interferes with the F3 fragment of the cloning scheme and when these sites are absent in a few select genomes, interfering sites pops up elsewhere in the genome that nevertheless still make the systems unworkable. The SARS-CoV-2 genome is the only one of which both the conventional and the no seems type IIS cloning methods would work with BsaI/BsmBI for the assembly of the genome—allowing both the easy assembly and ease for revision of the genome in all labs that were involved in the DEFUSE program.