Erythropoietin (EPO), also known as hematopoietin or hemopoietin, is a glycoprotein cytokine secreted by the kidney in response to cellular hypoxia; it stimulates red blood cell production (erythropoiesis) in the bone marrow. Low levels of EPO (around 10 mU/mL) are constantly secreted sufficient to compensate for normal red blood cell turnover. Common causes of cellular hypoxia resulting in elevated levels of EPO (up to 10 000 mU/mL) include any anemia, and hypoxemia due to chronic lung disease.
- The International Olympic Committee is trying to decide whether to ban artificial altitude training. It already prohibits other means by which athletes boost stamina by increasing their concentration of red blood cells, including blood transfusions and injections of erythropoietin (EPO), a hormone produced by the kidneys that stimulates red blood cell production. A synthetic version of EPO, developed to help dialysis patients, has become a popular if illicit performance enhancer for distance runners, cyclists, and cross-country skiers. The IOC instituted testing for EPO use at the Sydney games in 2000, but a new form of EPO gene therapy may prove more difficult to detect than the synthetic version. Scientists working with baboons have found a way to insert a new copy of the gene that produces EPO. Before long, genetically modified runners and cyclists may be able to generate higher-than-normal levels of their own natural EPO for an entire season or longer. Here is the ethical conundrum: If EPO injections and genetic modifications are objectionable, why isn’t Nike’s “altitude house” also objectionable? The effect on performance is the same—increasing aerobic endurance by boosting the blood’s capacity to carry oxygen to the muscles. It hardly seems nobler to thicken the blood by sleeping in a sealed room with thin air than by injecting hormones or altering one’s genes.
- Michael J. Sandel, The Case against Perfection (2007), Chap. 2 : Bionic Athletes, p. 33