Among the 4 structural proteins of CoVs, the S protein is a trimer composed of the S1 and S2 regions and is known to be the main protein that recognizes the receptor for initial entry into the host cell during infection; the S2 region of the S protein fuses with the viral and cell membranes after the S1 region of the S protein binds to the host receptor [17]. The gene discussed is PROS1; the disease is infection.