The spectrum of anemias treated with recombinant human erythropoietin is rapidly
broadening. Lifelong treatment with very high doses is now under evaluation for β-
thalassemia and sickle cell anemia. These indications make it worthwhile to search for
methods that will allow a permanent systemic delivery of the hormone. Here, we review
experimental gene-transfer-based procedures for erythropoietin delivery in vivo. In mice,
both ex vivo and direct in vivo approaches for gene transfer have resulted in the long-term …