Beta thalassemia is an inherited blood disorder that limits your body’s ability to make beta-globin. Beta-globin is an important protein needed to make hemoglobin and red blood cells. Beta thalassemia can cause you to experience anemia symptoms. Types include beta thalassemia major, beta thalassemia intermedia and beta thalassemia minor.
Beta thalassemia (pronounced “thal-uh-SEE-me-uh”) is a blood disorder that interferes with your body’s ability to make hemoglobin. Hemoglobin is an iron-rich protein that’s the main ingredient in red blood cells. Hemoglobin enables your red blood cells to carry oxygen to your body’s other cells and tissues. Your cells use the oxygen they receive from red blood cells to make energy.
Beta thalassemia is one of two main types of thalassemia. Beta thalassemia and its counterpart, alpha thalassemia, involve gene mutations (or errors) in the hemoglobin protein. This gene mutation disrupts your body’s ability to make a protein in hemoglobin called beta-globin.
Advertisement
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
Low production of beta-globin results in damage to your red blood cells, leading to their removal from blood circulation. If your body can’t make enough new red cells to replace the ones that are lost, anemia develops. Symptoms of anemia occur when there aren’t enough red blood cells to carry oxygen to your body’s tissues causing them to become deprived of oxygen.
Anemia symptoms associated with beta thalassemia can range from mild to severe, depending on how low your red blood cell count is.
Beta thalassemia is an inherited genetic disorder. Parents pass along the gene mutation to their biological children. Most people with beta thalassemia live in Africa, the Mediterranean region, the Middle East, India and Southeast Asia. With global migration, cases of beta thalassemia have increased in Northern Europe and North America.
Advertisement
Thalassemia is the most common inherited cause of anemia. Thousands of new beta thalassemia cases are diagnosed each year. Cases have declined as prevention measures, like screenings to identify people who carry thalassemia gene mutations, have increased.
Beta thalassemia results from a mutation (error) that limits beta-globin production in your body. Hemoglobin consists of four protein chains, two alpha-globin chains and two beta-globin chains. Mutations of the alpha-globin chain cause alpha thalassemia, while mutations of the beta-globin chain cause beta thalassemia. A deficiency of either globin chain damages and destroys the red blood cell.
You inherit the gene mutation for beta thalassemia in an autosomal recessive pattern. This happens when both biological parents carry one copy of the mutated gene and one copy of the normal gene. In the most severe form of beta thalassemia, you inherit a copy of the mutated gene from both parents.
In rare instances, inheriting just one mutated beta-globin gene causes beta thalassemia. This is called an autosomal dominant pattern.
Advertisement
The number of defective genes you inherit and the mutation’s location will determine your condition’s severity. Some mutations cause no beta-globin to be produced (beta-zero thalassemia). Other mutations cause too little beta-globin to be made (beta-plus thalassemia).
The types of beta thalassemia include the following.
Your symptoms will depend on how severe your beta thalassemia is. For instance, you may be asymptomatic (no symptoms) or have mild anemia symptoms with beta thalassemia minor. You may have moderate or more severe symptoms with beta thalassemia intermedia and especially beta thalassemia major.
Beta thalassemia minor (beta thalassemia trait) is associated with mild anemia symptoms, including:
The most severe symptoms are associated with beta thalassemia major. Some of these symptoms also appear with beta thalassemia intermedia, depending on your condition's severity. In addition to experiencing mild symptoms, you may have:
Infants with moderate to severe beta thalassemia may be especially fussy and get frequent infections.
Beta thalassemia is often diagnosed in childhood. Beta thalassemia major, the most severe form, is diagnosed early in childhood, by age 2. Your doctor will diagnose beta thalassemia based on your symptoms and blood test results.
Your doctor will diagnose beta thalassemia by performing a simple blood draw and analyzing the sample. Tests may include:
Your doctor may perform chorionic villus sampling (CVS) or amniocentesis during pregnancy if there’s a concern that your fetus may carry the mutated gene. CVS tests a portion of the placenta for signs of the gene mutation. The placenta is the organ that allows you and your fetus to share nutrients during pregnancy. Amniocentesis tests the fluid surrounding your fetus for signs of beta thalassemia.
You’ll likely work with a care team that includes multiple specialists. Working with an experienced hematologist, a specialist who treats blood disorders, is especially important.
Treatments may include:
The most common treatment complication is iron overload. Blood transfusions introduce more red blood cells and iron into your body. After many transfusions, excess iron can accumulate and damage vital organs like your liver, heart and pancreas. Talk with your doctor to determine how frequently you should receive iron chelation therapy to remove excess iron from your body if you’re receiving regular transfusions.
You can’t reduce your risk of inheriting the gene mutation associated with beta thalassemia. However, you can prevent passing it to your child. Talk to your doctor about screening for beta thalassemia if you or your partner are a potential carrier and considering having a baby.
The only known cure for beta thalassemia is a bone marrow and stem cell transplant from a compatible donor. Unfortunately, finding a compatible donor is often difficult. Even family members may not be considered compatible donors.
Researchers are currently studying other potential cures for beta thalassemia, such as replacing defective genes with healthy ones (gene therapy). This work is still in its early stages.
Beta thalassemia is treatable. With minor and moderate forms of beta thalassemia, you can expect an average lifespan if you follow your doctor’s treatment guidance. Beta thalassemia major can shorten your lifespan. The most common cause of death is heart failure due to iron overload.
Talk to your doctor about your prognosis based on the severity of your condition.
Ask your doctor how often you should receive blood tests and treatments. Ask about any lifestyle adjustments you should make to manage your condition.
Questions include:
A note from Cleveland Clinic
Your experience of beta thalassemia will depend on how severe your condition is. Regardless of the type of beta thalassemia, it’s important to work with specialists with experience diagnosing and treating thalassemia. Receiving the right treatments can help prevent anemia and reduce your risk of complications like iron overload. Working with a care team who’ll monitor your condition appropriately and provide a customized care plan can improve your prognosis.
Last reviewed on 07/20/2022.
Learn more about the Health Library and our editorial process.
Advertisement
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy