Notable examples include IgE‐dependent activation by mast cells [79], expression of cell‐adhesion molecules, activation of NKCs [80], and worsening of clinical symptoms related to rheumatoid arthritis (RA) in the morning, correlating with the daily rhythm of the proinflammatory cytokine IL‐6 [81]. The gene discussed is IGHE; the disease is rheumatoid arthritis.