FCGR3A and rheumatoid arthritis: No significant differences in NK-cell FcγRIIIa expression were demonstrated between FCGR3A genotypic groups in either HC (Kruskal–Wallis H test; p = 0.74; Supplementary Fig. S5e), RA (Kruskal–Wallis H test; p = 0.96; Supplementary Fig. S5f) or SLE (Mann–Whitney test; p = 0.21; Supplementary Fig. S5g).