Participation in the Studies of the Molecular Mechanisms of Bone Marrow Failure Our study is taking a comprehensive approach to the evaluation of participants, which is necessary to truly understand the genetic contribution to the development of disease. Individuals who wish to participate will be asked to: Sign a consent form indicating your desire to participate, Complete a written medical and family history questionnaire, Submit a sample of blood (we can provide kits so a physician can draw your blood), and Undergo a physical examination (for families in the St. Louis area only). Individuals will not be responsible for any costs associated with the study. The confidentiality of all study related materials will be maintained in accordance with State and Federal laws. To learn more about the study please contact the study coordinator: Jennifer Ivanovich, M.S., Study Coordinator: Washington University School of Medicine Box 8100, 660 W. Euclid Ave., St. Louis, Missouri 63110, USA Phone: 314-454-5076 jen@ccadmin.wustl.edu Monica Bessler, M.D., Ph.D., Co-Director Phone 314-362-8807 Mbessler@im.wustl.edu David Wilson, M.D., Ph.D. Co-Director Wilson_D@kids.wustl.edu