A genetic blood defect.
A genetic disease caused by a mutation in the code for one of the subunits of hemoglobin. Because of this mutation, the amino acid sequence of the protein is aberrant, which in turn affects its quatenary structure and its ability to carry oxygen. The name comes from the change in shape of the red blood cell. Instead of being round, it is sickle shaped.
Hereditary blood disease, occurring mostly in blacks, in which abnormal hemoglobin (hemoglobin HbS) causes red blood cells (erythrocytes) to become sickle-shaped, fragile, and nonfunctional, leading to anemia. Persons inheriting the trait from only one parent may show few symptoms; those homozygous for the trait (inheriting it from both parents) have chronic anemia, an enlarged spleen, lethargy, weakness, blood clot formation, and joint pain.
Hereditary hemoglobinopathy, with partial or complete replacement of normal hemoglobin with abnormal hemoglobin.
An inherited, chronic blood disorder that alters the shape of red blood cells and causes them to function abnormally; also known as sickle cell disease. The cause of the disease is an abnormality in hemoglobin, the pigment in red blood cells that transports oxygen. After they give up their oxygen, molecules of the abnormal hemoglobin, called hemoglobin S, tend to clump into rods that deform the normally round red blood cells into sickle shapes. Unable to squeeze through small blood vessels because of their shape, the sickle cells block blood flow, causing tissue and organ damage and pain. In addition, the sickle cells have a life span of only 10 to 12 days versus 120 days for normal red blood cells. The body cannot replace them fast enough, resulting in anemia, an ongoing decline in red blood cells.
An inherited disorder transmitted as an autosomal recessive trait that causes an abnormality of the globin genes in hemoglobin. The frequency of the genetic defect responsible for this chronic anemia disorder is highest among African-American, native African, and Mediterranean populations. The disease also affects people from the Caribbean and Central and South America. Approximately 75,000 people in the U.S. have sickle cell anemia. The illness affects one of every 500 African-American babies. Roughly 8% of the African-American population carries the sickle cell trait. Sickle cell anemia during pregnancy increases the risk of crisis, pre-eclampsia, urinary tract infection, congestive heart failure, and pulmonary infarction. Use of supplemental oxygen during labor is recommended.