The observation that recombinant EPO improves the exercise capacity of anemic hemodialyzed patients who were still transfusion independent [87] paved the way to devise therapeutic uses for EPO to improve the quality of life of patients with a great variety of pathological conditions, ranging from the anemia of the elderly caused by chronic inflammation to that sustained by the chemotherapy used to halt disease progression in cancer patients. This evidence concerns the gene EPO and anemia (phenotype).