The median serum immunoglobulin values of all patients at time t0 amounted to 500 mg/dl for IgG (n = 89, without MM patients), 62 mg/dl for IgA (n = 87, without MM patients) and 26.5 mg/dl for IgM (n = 98, without patients suffering from Waldenstrom macroglobulinemia). The gene discussed is CD79A; the disease is Waldenstrom macroglobulinemia.