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Beta thalassemia (thal-uh-SEE-me-uh) is an inherited blood disorder in which the body has a problem producing beta globin, a component of hemoglobin, the protein in red blood cells (RBCs) that transports oxygen throughout the body.

More to Know

Hemoglobin contains two chains of alpha globin and two chains of beta globin. Beta thalassemia happens when one of the genes controlling beta globin production is absent or defective, causing faster than normal destruction of RBCs. This leads to anemia, which can cause fatigue and other complications, including bone deformities, slower growth rates, and organ damage.

There are three types of beta thalassemia, depending on whether one or two beta globin genes are mutated, and the severity of the mutations:

1. Beta thalassemia minor (or beta thalassemia trait) is when one beta globin gene is mutated. It usually causes mild anemia and requires no treatment.
2. Beta thalassemia major (Cooley’s anemia) is when both of the beta globin genes are mutated. This is the most severe form of beta thalassemia. Babies who have it often seem healthy at first, but develop symptoms within the first 2 years of life. It’s treated with regular blood transfusions.
3. Beta thalassemia intermedia is when both beta globin genes are mutated, but the mutations are less severe. It usually causes moderately severe anemia and sometimes requires regular blood transfusions.

Treatment depends on the severity of the symptoms and may include blood transfusions and folic acid supplements. A bone marrow transplant is the only known cure for beta thalassemia, but since transplants carry many risks, they are usually done only in the most severe cases of thalassemia.

Keep in Mind

For many people with beta thalassemia trait, whose only symptom may be mild anemia from time to time, no medical treatment is necessary. Those who have a more severe type of the disease can reduce the risk of complications by eating a balanced diet, getting regular physical activity, taking steps to prevent colds or flu, and going to all their medical appointments as recommended.

All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.