Sickle Cell Disease
Sickle-cell disease is a genetic disorder that affects the blood. The mutation that causes the disorder affects the production of an important protein called hemoglobin. Hemoglobin is the protein in red blood cells that carries oxygen. People with sickle-cell disease produce an abnormal form of hemoglobin. When oxygen concentrations are low, their red blood cells have an unusual sickle shape.
Sickle-shaped red blood cells cannot carry as much oxygen as normal-shaped cells. Because of their shape, the cells become stuck in narrow blood vessels, blocking them. People with sickle-cell disease suffer from lack of oxygen in the blood and experience pain and weakness.
The allele for the sickle-cell trait is most common in people of African ancestry. About 9 percent of African Americans carry the sickle-cell allele. The allele for the sickle-cell trait is codominant with the normal allele. A person with two sickle-cell allele will produce both normal hemoglobin and abnormal hemoglobin. This person usually will not have symptoms of the disease.
Currently, there is no cure for sickle-cell disease. People with sickle-cell disease are given drugs to relieve their painful symptoms and to prevent blockages in blood vessels. As with cystic fibrosis, scientists are hopeful that new, successful treatments will soon be found.
Normally, red blood cells are shaped like round disks. In a person with sickle-cell disease, red blood cells can become sickle-shaped.
Sickle-shaped red blood cells cannot carry as much oxygen as normal-shaped cells. Because of their shape, the cells become stuck in narrow blood vessels, blocking them. People with sickle-cell disease suffer from lack of oxygen in the blood and experience pain and weakness.
The allele for the sickle-cell trait is most common in people of African ancestry. About 9 percent of African Americans carry the sickle-cell allele. The allele for the sickle-cell trait is codominant with the normal allele. A person with two sickle-cell allele will produce both normal hemoglobin and abnormal hemoglobin. This person usually will not have symptoms of the disease.
Currently, there is no cure for sickle-cell disease. People with sickle-cell disease are given drugs to relieve their painful symptoms and to prevent blockages in blood vessels. As with cystic fibrosis, scientists are hopeful that new, successful treatments will soon be found.
Normally, red blood cells are shaped like round disks. In a person with sickle-cell disease, red blood cells can become sickle-shaped.