SLE patients had decreased levels of apoM compared to healthy controls (p < 0.01), with apoM levels correlating inversely with SLEDAI (r = − 0.31, p < 0.01) as well as with levels of CRP (r = − 0.26, p = 0.02) and positively with levels of C3 (r = 0.29, p < 0.01). The gene discussed is C3; the disease is systemic lupus erythematosus.