In hemodialysis (HD) patients requiring anemia management, the 3-fold longer terminal half-life (25.3 hours) of darbepoetin-alpha (DA) results in reduced dose frequency when compared with recombinant human erythropoietin (EPO) -alpha or -beta by intravenous administration (8.5 hours). The gene discussed is EPO; the disease is anemia (phenotype).