Thalassemia is a disorder that causes decreased numbers of red blood cells and smaller amounts of hemoglobin (an important protein in the red blood cell). In order to treat thalassemia, bone marrow transplants (also known as stem cell transplants) can be used. Bone Marrow Transplant uses transplanted bone marrow and/or stem cells to replace the bone marrow of the patient. Replacing the old bone marrow with new healthy cells allows for the formation of normal red blood cells. In order to transplant the new healthy cells, the old cells are first destroyed using chemotherapy or radiation; then, the new cells can be implanted.