I think I mentioned this in another post but since you guys are talking about prion proteins I will post the link again: https://ijvtpr.com/index.php/IJVTPR/arti....
On page 22 they have a section 'A Possible Link to Prion Diseases and Neurodegeneration'.
'... The bovine prion linked to MADCOW has a spectacular sequence of ten GxxxGs in a row (see uniprot.org/uniprot/P10279).
...
When considering that the SARS-CoV-2 spike protein is a transmembrane protein, and that it contains fiveGxxxG motifs in its sequence (see uniprot.org/uniprot/P0DTC2), it becomes extremely plausible that it could behave as a prion. One of the GxxxG sequences is present within its membrane fusion domain. Recall that the mRNA vaccines are designed with an altered sequencethat replaces two adjacent amino acids in the fusion domain with a pair of prolines. This is done intentionally in order to force the protein to remain in its open state and make it harder for it to fuse with the membrane. This seems to us like a dangerous step towards misfolding potentially leading to prion disease.'