Complement inhibition, achieved by using eculizumab, a humanized monoclonal antibody that prevents C5 activation and improve diseases outcomes (19), has been used to treat autoinflammatory (e.g., atypical hemolytic uremic syndrome and paroxysmal nocturnal hemoglobinuria) and autoimmune conditions (e.g., myasthenia gravis). The gene discussed is C5; the disease is myasthenia gravis.