INDEPENDENCE DAY. On July 4, 1776, the thirteen colonies claimed their independence from England, an event which eventually led to the formation of the United States.
Polycythemia vera is a rare, chronic disorder involving the overproduction of blood cells in the bone marrow (myeloproliferation). The overproduction of red blood cells is most dramatic, but the production of white blood cells and platelets are also elevated in most cases.
1 Polycythemia vera (PV) is related to a genetic mutation in the JAK2 gene, which is thought to increase the sensitivity of bone marrow cells to Epo, resulting in increased red blood cell production. 2  Levels of other types of blood cells (white blood cells and platelets) are also often increased in this condition.