Vaccine-specific IgG and Fc gamma receptor (FcγR) engagement were characterised via bead-based multiplex array.<h4>Results</h4>Following two COVID-19 vaccine doses, G1m1,17<sup>+/+</sup> compared to G1m-1,3<sup>+/+</sup> vaccinees had increased IgG and FcγR engagement specific for the antigenically conserved SARS-CoV-2 Spike 2 (S2) domain. The gene discussed is FCGR2A; the disease is COVID-19.