Specifically, the Kidney Disease Improving Global Outcomes (KDIGO) guidelines recommend Hb level to be maintained between 9 and 11.5 g/dl [3]; the European Best Practice Guidelines recommend that most persons with CKD achieve a target Hb between 11 and 12 g/dl [4]; the National Institute for Health and Clinical Excellence (NICE) recommends a target range between 10 and 12 g/dl [5]. This evidence concerns the gene GSTM1 and chronic kidney disease.