Which type of mutation causes sickle cell anemia

Sickle cell anemia is an inherited form of anemia, a disease that is characterized by inadequate healthy red blood cells to transport an adequate level of oxygen throughout the body.

Normally, red blood cells are flexible and round, and move easily through the blood vessels. In sickle cell anemia, red blood cells become stiff and sticky, and they are sickle-shaped or crescent-shaped. These irregularly shaped cells can get stuck in small blood vessels, which can slow or block the flow of blood and oxygen to different parts of the body.

This disease occurs due to mutations in the HBB gene, located on the short arm of chromosome 11, which encodes the beta-globin protein. This beta-globin is a subunit of hemoglobin which is found in blood erythrocytes.

Hemoglobin allows red blood cells to carry oxygen from the lungs to the entire body. In sickle cell anemia, abnormal hemoglobin causes red blood cells to become stiff, stocky and deformed.

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