GSTM1 and anemia (phenotype): Unexpectedly, the recent randomized controlled trials Correction of Hemoglobin and Outcomes in Renal Insufficiency (CHOIR) [60] and Cardiovascular Risk Reduction by Early Anemia Treatment with Epoetin (CREATE) [61] showed unforeseen increases in cardiovascular events [60] and dialysis initiation [61] among patients assigned to the highest Hb targets, prompting reexamination of the optimal targets and appropriate recipients of erythropoietic therapies.