Three types of nephropathy have been reported in patients with hepatitis C virus (HCV) infection, including IgG-dominant nephropathies (such as membranous glomerulonephritis: MGN), IgA-dominant nephropathies (such as IgA nephropathy), and IgM-dominant nephropathies (such as type 1 membranoproliferative glomerulonephritis (MPGN), which corresponds to cryoglobulinemic glomerulopathy). The gene discussed is CD79A; the disease is kidney disorder.