Sickle Cell Anemia (SCA) is the most common type of Sickle Cell disease. It is primarily seen in African Americans and individuals of Indian, Mediterranean, and Saudi Arabian descent, but can occur in anyone. One in every 400 African Americans has Sickle Cell Anemia, and one out of every ten carries the trait.
Sickle Cell disease is a group of red blood cell disorders, and is caused by a substitution of a single amino acid in the protein, hemoglobin. There are millions of hemoglobin proteins in red blood cells. Normal red blood cells which are round like disks move through small blood vessels in the body to deliver oxygen. However, the hemoglobin in the red blood cells of an individual with sickle cell disease causes the red blood cells to become hard, sticky and shaped like sickles (a tool used to cut wheat). The sickle hemoglobin crystallizes when the blood deoxygenates. When these hard and pointed red cells go through the small blood vessels, they clog the flow and break apart. This disturbs the life of an individual with this disease by causing pain, damage and a low blood count, or anemia.
The photograph above is of a healthy red blood cell and a sickle one. The sickle cell is crescent shaped.
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