Only older Ikzf2−/− mice at the age of 6–8 months spontaneously developed an autoimmune phenotype resembling some features of systemic lupus erythematosus (SLE) with infiltration of lymphocytes to non‐lymphoid organs, production of autoantibodies, and glomerulonephritis [41, 42]. The gene discussed is IKZF2; the disease is systemic lupus erythematosus.