Sickle Cell Anemia: A Curse and a BlessingSickle Cell Anemia is a disease found right here in America, but in low levels compared to some areas of the world. The rate for this disease is around five times greater in certain places in Africa. That is because the potentially fatal disease Sickle Cell Anemia can also work as a sortof vaccination for another disease called malaria. First the mechanics of Sickle Cell Anemia willbe discussed, then its possible benefits. Sickle Cell Anemia is an inherited condition. One gene for Sickle Cell Anemia must be inherited from each parent in order to have the disease. A person who receives a gene for Sickle Cell Anemia from one parent and a normal gene from the other has a condition called sickle cell trait. Sickle cell trait produces no symptoms or problems for most people. Sickle Cell Anemia can neither be contracted nor passed on to another person. The severity of sickle cell disease varies greatly. Some people with sickle cell disease lead lives that are nearly normal. Others are less fortunate, and can suffer from a variety of conditions. Sickle Cell Anemia is caused by a change in the chemical composition of the protein hemoglobin which is responsible for delivering oxygen throughout our bodies. Normal hemoglobin is found as a round shape, and is composed of four proteins – two alpha chains and two beta chains. The change that causes Sickle Cell Anemia occurs when an amino acid called valine is substituted for glutamic acid in both of the beta chains. This change in the composure of hemoglobin causes the shape to change when under certain conditions. Two of these conditions are low oxygen and dehydration. The hemoglobin of a person with Sickle Cell Anemia then becomes elongated and curved, hence the name sickle cell. When this happens many problems can occur, primarily blood clotting which leads to a lack of oxygen in body tissues. Other negative affects of Sickle Cell Anemia are a weakened heart because it is constantly overworked. Also, bone marrow is affected and bones become softer than usual. While there is no cure for Sickle Cell Anemia there is treatment. The primary goal is to reduce the frequency of the Sickle Cell Anemia crisis episodes and maintain enough red blood cells to keep body tissues healthy. Adequate hydration, oxygenation, bone marrow stimulation, and blood transfusions are commonly used to treat Sickle Cell Anemia. In the United States, about one in five hundred African Americans develop sickle cell anemia. In Africa, about one in one hundred individuals develop the disease. Why is the frequency of a potentially fatal disease so much higher in Africa? The answer is related to another potentially fatal disease, malaria. Malaria is characterized by chills, fever, vomiting, and severe headaches. Malaria is caused by a parasite called Plasmodium that is transmitted to humans by a mosquito. When malaria parasites invade the bloodstream, the red cells that contain defective hemoglobin because of Sickle Cell Anemia become sickled and die. This effectively protects theindividual with Sickle Cell Anemia from an infection of malaria. This explains why areas if the world with a high rate of malaria, such as Africa, also have a high rate for Sickle Cell Anemia. Sickle Cell Anemia is nature’s version of irony. On one side of the coin is the answer to malaria, a disease that has plague regions of the world for centuries; but sadly the other side of the coin is possibly
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