During the diagnostic period, since the patient had discontinued the specific therapy for myeloma for about one month, it has highlighted also a serological progression of disease with increase of the MC to 24 g/L, decrease of Hb (100 g/L) and albumin (17 g/L), alteration of k/λ free light chain ratio (34.12), and increase of bone marrow plasma cell infiltration to 30%. The gene discussed is GSTM1; the disease is plasma cell myeloma.