Prior to the identification of the key role of FcγRIIb in mediating the suppressive actions of IgG on mast cells and basophils, this steric blocking effect had commonly been presumed to be the dominant inhibitory mechanism of IgG in allergy, especially following SCIT, which is why such IgG antibodies are still commonly referred to as blocking IgG. Here, FCGR2B is linked to Allergy.