Thalassemia is an inherited genetic blood disorder that causes mild to severe anemia. The anemia in thalassemia occurs not because of a lack of iron but because of a problem with the production of hemoglobin in the red blood cells. Individuals with thalassemia do not have enough hemoglobin or red blood cells to transport oxygen throughout the body. Mild or moderate forms of thalassemia may not require any treatment. The most common form of severe thalassemia in the United States is beta thalassemia major, also known as Cooley’s anemia. Treatment usually includes frequent blood transfusions coupled with iron chelation therapy to remove the iron that accumulates in the body from the transfusions.