Recently, polymorphisms of FCRL3 have been reported to be associated with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) [17], Behcet’s disease [18], autoimmune thyroid disease (AITD) [17,19], and multiple sclerosis (MS) [20,21]. The gene discussed is FCRL3; the disease is myeloid sarcoma.