The study (NCT01147666) was a two-part study and included hemodialysis-treated anemia and terminal renal failure patients who had previously received erythropoietin and intravenous iron for 4 weeks prior to randomization, showing an average Hb level of 9–13.5 g/dL for 8 weeks [10]. The gene discussed is GSTM1; the disease is anemia (phenotype).