Sickle Cell

Sickle cell disease is a disorder of the blood and, consequently, the circulatory system. Sickle cell affects what is known as hemoglobin in the red blood cell. Hemoglobin's function is to carry oxygen within the cell and transport to where it is needed. But in an affected sickle cell, the red blood cell is misshapen, appearing in a crescent moon or sickle shape. A normal red blood cell is pliant and round, which enables it to easily flow through the bloodstream, whereas a sickle cell is rigid and, due to its shape, causes a clot to form in a blood vessel.

Sickle cell disease develops in a person when he or she receives the sickle cell trait from their mother and father. If a person only receives the trait from one parent, the child merely becomes a carrier of the affliction. Usually, there are enough normal red blood cells in the body to carry oxygen from the lungs to the places where it is used. On the other hand, if a child receives the trait from both parents, they develop sickle cell anemia. This disease can adversely affect the internal organs and can even cause death.

Sickle cell anemia requires extensive treatment in order for a patient to lead a relatively normal life. Medical operations are always a great danger, and special care must be taken before and after dental exams and pregnancy, as well. Testing for sickle cell disease is important because a parent, passing the disease to his or her offspring, can endanger the life of the child. A simple test, a hemoglobin electrophoresis test, can readily identify carriers of the trait and carriers of the disease. It is also possible to test unborn babies who are at least in their eleventh week of pregnancy due to recent innovations in medicine.

Of late, it has been argued that sickle cell anemia has developed in the human population, not because of some deficiency, but because of the positive aspects of natural selection. Evidence suggests that the disease developed in the presence of malaria as it swept through the population, killing its hosts. Those who had sickle cell anemia were left unscathed by malaria because it was unable to attack the misshapen red blood cells. So, in effect, the malady had proven to be life-saving. Controversy still surrounds the validity of this hypothesis, as experiments of the past seem to support and negate the view, though more work will be done in the area.