Gene HBB
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Also known as
beta-globin, hemoglobin subunit beta, HbS, sickle cellOverview
HBB (Hemoglobin Subunit Beta) encodes the beta chain of hemoglobin, the oxygen-carrying protein in red blood cells. Each hemoglobin molecule contains two alpha and two beta chains, and proper function of beta-globin is essential for oxygen transport throughout the body.Mutations in HBB cause several important hemoglobin disorders. Sickle cell disease results from the HbS mutation (E6V), causing red blood cells to form a sickle shape under low oxygen conditions, leading to vaso-occlusive crises and organ damage. Beta-thalassemia results from mutations that reduce or eliminate beta-globin production, causing severe anemia requiring regular transfusions. Both conditions are common in regions where malaria is endemic, as carriers have some protection against malaria.
Understanding your HBB genetic status is critical for carrier screening, particularly for individuals of African, Mediterranean, Middle Eastern, or South Asian ancestry. Identifying carriers before pregnancy allows informed reproductive decisions and preparation for affected offspring.