Sickle cell disease other genetic diseases) among African Americans compared to West Africans. Another factor that limits the spread of sickle cell genes in North America is the relative absence of polygamy, which allows affected males to continue to produce many children with multiple partners. The loss of red blood cell elasticity is central to the pathophysiology of sickle cell disease. Normal red blood cells are quite elastic, which allows the cells to deform to pass through capillaries. In sickle cell disease, low oxygen tension promotes red blood cell sickling and repeated episodes of sickling damage the cell membrane and decrease the cell's
Blood cell are based on the inappropriate production of white blood cells. Platelets, or "thrombocytes", are very small, irregularly shaped clear cell fragments, 2–3 µm in diameter, which derive from fragmentation of megakaryocytes. The average lifespan of a platelet is normally just 5 to 9 days. Platelets are a natural source of growth factors. They circulate in the blood of mammals and are involved in hemostasis, leading to the formation of blood clots. Platelets release thread-like fibers to form these clots. If the number of platelets is too low, excessive bleeding can occur. However, if the number of platelets is too high,