Sickle cell disease is an inherited blood disorder. Normally,
red blood cells are disc-shaped and flexible. In sickle cell
disease, however, hemoglobin (the chemical within red blood
cells that carries oxygen around the body) is abnormal. This
causes red blood cells to collapse into a crescent or sickle
shape. It also causes the red blood cells to be abnormally stiff
and fragile. These elongated, stiff red blood cells have a
tendency to clump together and clog up small blood vessels
throughout the body. When blood vessels are blocked by sickle-
shaped red blood cells, parts of the body are deprived of
oxygen. This can cause severe pain and damage to the organs and
tissues that are deprived of oxygen. Furthermore, abnormal red
blood cells are destroyed at an unusually high rate, causing a
shortage of red blood cells (called anemia). Sickle cell disease
is a genetic disorder. If you receive two defective genes (one
from each of your parents), you will have sickle cell disease.
If you only have one defective gene