To do the bone marrow transplant, we must first kill the cells in the bone marrow that make the abnormal red blood cells that are found in patients with severe thalassemia or sickle cell disease.~We will do this by using three drugs: busulfan, cyclophosphamide, and CAMPATH-1H. CAMPATH-IH is an investigational drug. CAMPATH-1H is used to prevent participants from rejecting or refusing to let the donor blood cells grow in the body. After the drug treatment, participants will be given bone marrow from a brother or sister who has healthy bone marrow that matches.
The major goal of this study is to determine the risks and benefits of bone marrow transplants in patients with severe thalassemia or sickle cell disease. Participation in this project will be for two years.