Beta Thalassemia

Beta thalassemia is type of inherited blood disorder that affects the production of hemoglobin in the body, which can cause anemia, fatigue, jaundice, and other symptoms. Worldwide, the condition is fairly common. However, in the United States, beta thalassemia is less common, affecting no more than 1,000 people. The disease is often treated with blood transfusions, iron chelation therapy, and bone marrow transplants.

 

What Is Beta Thalassemia?

Thalassemia is a type of inherited blood disorder that can cause anemia. It affects a person's ability to produce hemoglobin, which is the protein in red blood cells that delivers oxygen to all parts of the body. There are two main types of thalassemia: alpha thalassemia and beta thalassemia.
 
Hemoglobin is made up of two different protein chains: the alpha-globin chain and the beta-globin chain. Alpha thalassemia occurs when there is a problem with the alpha-globin chain, and beta thalassemia occurs when there is a problem with the beta-globin chain.
 

How Common Is Beta Thalassemia?

Worldwide, beta thalassemia is considered a fairly common blood disorder, affecting thousands of infants each year. The condition occurs most frequently in:
 
  • Mediterranean countries
  • North Africa
  • The Middle East
  • India
  • Southeast Asia.
 
In North America, beta thalassemia is less common, where an estimated 750 to 1,000 people have the condition.
 

Common Symptoms of Beta Thalassemia

Beta thalassemia major has more severe signs and symptoms than those seen with beta thalassemia intermedia.
 
Signs and symptoms of beta thalassemia major typically appear in the first two years of life. Symptoms include:
 
  • Pale and listless appearance
  • A poor appetite
  • Slow growth development
  • Jaundice (yellowing of the skin)
  • Enlarged spleen, liver, and heart.
 
Adolescents with the severe form of beta thalassemia may experience delayed puberty.
 
Individuals with beta thalassemia intermedia may not have any symptoms, or their symptoms may be mild throughout childhood and adolescence.
 
(Click Symptoms of Beta Thalassemia for more information.)
 

Causes of Beta Thalassemia

Beta thalassemia is caused by mutations in the hemoglobin beta (HBB) gene. As mentioned, hemoglobin is made up of two different kinds of protein chains, one of which is the beta hemoglobin chain. Mutations in the HBB gene can reduce or stop the production of beta hemoglobin, which leads to abnormal hemoglobin that cannot carry oxygen to the tissues and organs in the body.
 

How Is Beta Thalassemia Inherited?

Beta thalassemia major and beta thalassemia intermedia are inherited in an autosomal recessive pattern, which means that an abnormal gene from each parent is required to cause the disease.
 
In most cases, the parents of an individual with an autosomal recessive disorder are carriers of one copy of the altered gene, but do not show symptoms of beta thalassemia. However, there are cases in which carriers of the altered HBB gene have a mild anemia referred to as beta thalassemia minor.
 
In a small percentage of families, the HBB mutation is inherited in an autosomal dominant manner, which means that only one abnormal gene in each cell is needed to cause beta thalassemia.
 
(Click How Is Thalassemia Inherited? for more information about the inheritance of the abnormal gene that causes beta thalassemia.)
 

Treating Beta Thalassemia

Treatment for beta thalassemia will depend on the type and severity of the disease. Examples include:
 
  • People who are carriers of the thalassemia trait usually have no symptoms and do not need treatment for beta thalassemia.
 
  • Those with moderate forms of the disease may need occassional blood transfusions.
 
  • Those with severe beta thalassemia have a serious and life-threatening illness. They are treated regularly with blood transfusions, iron chelation therapy, and bone marrow transplants. Without treatment, children with severe beta thalassemia do not generally live beyond early childhood.
 
Bone marrow or stem cell transplants have cured beta thalassemia in some children. However, this treatment option is not available for most people with beta thalassemia.
 
Thalassemia research scientists are studying new treatments for the condition, including ways to cure thalassemia through stem cell and gene therapies.
 

Living With Beta Thalassemia

If you have moderate or severe beta thalassemia, you need to take good care of your health. Some suggestions for living with beta thalassemia include:
 
  • Follow your treatment plan and see your doctor regularly for checkups and treatment.
  • If you have regular blood transfusions and iron chelation therapy, it is important to continue with treatment as recommended.
  • If you have regular blood transfusions, you should avoid taking vitamins or other supplements containing iron.
  • Maintain a healthy diet. Your doctor may also give you a folic acid (a B vitamin) supplement to take every day in order to help your body make new red blood cells.
  • Get a flu shot every year and the pneumococcal vaccine to prevent infections.
 

Other Names for Beta Thalassemia

Other names for beta thalassemia include:
 
  • Beta thalassemia minor (also called thalassemia minor or thalassemia trait)
  • Beta thalassemia intermedia (also called thalassemia intermedia or mild Cooley's anemia)
  • Beta thalassemia major (also called thalassemia major or Cooley's anemia)
  • Mediterranean anemia.
 

Beta Thalassemia: A Summary

Important information to keep in mind regarding beta thalassemia includes:
 
  • Thalassemia is a group of inherited blood disorders that can cause mild to severe anemia. It occurs when there are problems with the production of hemoglobin in red blood cells. As a result, a person with thalassemia does not have enough hemoglobin or red blood cells to carry oxygen throughout the body.
 
  • There are two main types of thalassemia: alpha and beta thalassemia. Alpha thalassemia occurs when there is a problem with the alpha-globin chain that is part of hemoglobin. Beta thalassemia occurs when there is a problem with the beta-globin chain.
 
  • There are mild, moderate, and severe forms of beta thalassemia. The most common severe form of thalassemia seen in the United States is beta thalassemia major (Cooley's anemia). Cooley's anemia mainly affects people from Mediterranean countries and Asia.
Add this article to your Favorites     Email this article     Print
Written by/reviewed by: Arthur Schoenstadt, MD
Last reviewed by: Arthur Schoenstadt, MD