On the other hand, C1q exists as a pentameric C1qC1r2C1s2 complex (178, 179), and how C1r/C1s deficiency also leads to monogenic SLE, like C1q deficiency, is not explained by the phagocytosis hypothesis (164, 181, 182). The gene discussed is C1R; the disease is systemic lupus erythematosus.