By immunofluorescence, different patterns are observed: linear deposition of IgG along the glomerular basement membrane in Goodpasture syndrome, where pulmonary hemorrhage is life-threatening; granular deposition of IgG and C3 in lupus disease, cryoglobulinemia, and endocarditis; IgA deposition in Henoch–Schonlein disease; and no significant immune deposition in ANCA-associated vasculitis. The gene discussed is C3; the disease is cryoglobulinemia.