Sickle cell anemia is an inherited disease. People who have the disease inherit two genes for sickle hemoglobin—one from each parent.
Sickle hemoglobin causes red blood cells to develop a sickle, or crescent, shape. Sickle cells are stiff and sticky. They tend to block blood flow in the blood vessels of the limbs and organs. Blocked blood flow can cause pain and organ damage. It can also raise the risk for infection.
People who inherit a sickle hemoglobin gene from one parent and a normal gene from the other parent have sickle cell trait. Their bodies make both sickle hemoglobin and normal hemoglobin.
People who have sickle cell trait usually have few, if any, symptoms and lead normal lives. However, some people may have medical complications.
People who have sickle cell trait can pass the sickle hemoglobin gene to their children. The following image shows an example of an inheritance pattern for sickle cell trait.
When both parents have a normal gene and an abnormal gene, each child has a 25 percent chance of inheriting two normal genes; a 50 percent chance of inheriting one normal gene and one abnormal gene; and a 25 percent chance of inheriting two abnormal genes.
Living With and Managing Sickle Cell Disease (Nicholas)
Clinical trials are research studies that explore whether a medical strategy, treatment, or device is safe and effective for humans. To find clinical trials that are currently underway for Sickle Cell Anemia, visit www.clinicaltrials.gov.
Visit Children and Clinical Studies to hear experts, parents, and children talk about their experiences with clinical research.
NHLBI-supported research has helped reduce the burden of sickle cell disease. Learn more about how this research has benefited Tiffany McCoy and others who are living with sickle cell disease in the NHLBI’s stories of success.
December 9, 2013
Gary H. Gibbons
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