An unprecedented mink cull has been ordered in Denmark amid the outbreak of SARS-CoV-2 in these farmed animals. The plan was announced after scientists discovered a widespread Y453F mutation in the spike protein, that has been passed from animal to humans.

This mutation is of particular concern because it occurs at a conservative domain of the receptor-binding domain (RBD) directly involved in ACE2 binding. Results from some preliminary studies suggest the Y453F mutation affects the ability of the Spike protein to bind with ACE2, while others demonstrate that the mutated spike can escape from detection from a commercial anti-S antibody.

Although there is still no clear evidence indicating this mutation or any other mutation like the popular D614G, has any clinical significance, the characteristics of the mutations need to be thoroughly investigated in the context of vaccine and antibody therapy.

Sino Biological has launched the recombinant Y453F RBD protein. This product is the newest addition to a large library of recombinant spike variants. These proteins can be used to evaluate the efficacy of the antibodies and vaccination.