PLCG2 and agammaglobulinemia: A gain of function mutation in PLCG2 gene is associated with phospholipase Cγ2 (PLCγ2)-associated antibody deficiency and immune dysregulation (APLAID), dominant inherited disorder, and auto-inflammation (61), thereby suggesting that PLCG2 might be a potential therapeutic target for controlling inflammation during RA pathogenesis.