This study that will allow for the preservation and/or storage of a small portion one or more of the following tissues:

• Peripheral blood
• Bone marrow
• Bone marrow biopsy
• A phlebotomized unit of blood
• Spleen cells
• Toenail clippings

This material will be used for the study of Myeloproliferative Disorders (MPD) by researchers. The goals of this research study are to understand the causes of MPDs, how to diagnose them more easily and how to treat them better. MPD is a disease affecting hematopoietic stem cells. Hematopoietic stem cells are cells that make blood cells. These stem cells grow in the center portion of the bones called bone marrow. Under some conditions, these cells are also found in blood. There are several diseases, which are classified as MPD. These include polycythemia vera (too many red blood cells), essential thrombocythemia (too many platelets), and idiopathic myelofibrosis (abnormal blood cells and fibers build up in the bone marrow). These syndromes carry a high risk of developing leukemia. It is important to continue to learn more about these blood cancers and to learn more about the effectiveness and potential side effects of various treatments.

Inclusion Criteria:

• Patients diagnosed with Philadelphia chromosome negative myeloproliferative disorders (MPD) polycythemia vera (PV), idiopathic myelofibrosis (IM), and essential thrombocythemia (ET) are eligible.
• Newly diagnose MPD patients as well as previously treated for a MPD are eligible.
• Signed informed consent is required from each patient at the time of enrollment.

Exclusion Criteria:

• Patients currently participating in experimental treatment arms of MPD-RC protocols, or other experimental treatment protocols are not eligible during the period they are on study.

Patients diagnosed with Philadelphia chromosome negative myeloproliferative disorders (MPD) polycythemia vera (PV), idiopathic myelofibrosis (IM), and essential thrombocythemia (ET) are eligible and not currently participating in any MPD-RC treatment studies.