In RA, rheumatoid factor (RF) as well as the anti-citrullinated peptide antibody (ACPA) are often of the IgG subtype, and, as such, can be recognized by Fcγ receptors (FcγR) on immune cells such as monocytes and macrophages [1,4,5]. Here, FCGR2A is linked to rheumatoid arthritis.