Understanding the Beta Thalassemia Minor Trait
Medically reviewed by Gagandeep Brar, MD
Beta thalassemia minor—also known as beta thalassemia trait or B thalassemia—is a blood disorder. It lowers your blood's level of hemoglobin, an iron-containing protein in red blood cells that carries oxygen throughout your body.
The red blood cells in people with this condition are smaller than normal. Those with this problem can go through life healthy and without symptoms. For some, though, it can lead to mild anemia, though it rarely needs treatment.
This problem is passed from parent to child. You can carry the trait and pass it to your child without knowing it. Some only learn about it when they have a blood test for other problems.
This article describes how beta thalassemia is passed from parent to child, the symptoms that can occur, and when treatment is needed.
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Carrying or Inheriting the Beta Thalassemia Minor Trait
The beta thalassemia trait is present at birth. It is inherited in an autosomal recessive pattern involving the HBB (hemoglobin subunit beta) gene. Your chances of carrying or inheriting the beta thalassemia minor trait depend on whether one or both of your parents are carriers.
In an autosomal recessive condition like beta thalassemia minor, inheriting one normal HBB gene can compensate for inheriting one mutated (defective) gene. In this scenario, the baby will be a carrier (because they have the trait) but usually without symptoms (due to the work of the normal HBB gene).
If both parents have beta thalassemia trait, each child has the following risk:
25% chance of being affected with beta thalassemia trait
50% chance of being an asymptomatic carrier
25% chance of being unaffected and not a carrier
An official diagnosis of beta thalassemia minor can be confirmed only by a healthcare provider. Diagnosis is usually done using the following laboratory tests:
Complete blood count (CBC): A blood test that measures the size, shape, and number of your red blood cells
Hemoglobin electrophoresis: A specialized blood test that measures the different types of hemoglobin in your blood
Iron studies: Such as free erythrocyte protoporphyrin and ferritin blood tests
State-mandated newborn screening: Depending on whether your state tests for hemoglobin disorders at birth
Chorionic villus sampling (CVS) or amniocentesis: For a fetus in which beta thalassemia is suspected
Molecular genetic testing can detect mutations of the HBB gene. However, this type of testing is typically reserved to identify people at risk of having the trait and those who are asymptomatic carriers. It may also be used in prenatal testing.
Knowing whether you have the thalassemia trait is important for family planning and your own health. Two people with the trait increase their risk of passing two defective HBB genes to their baby. This can result in beta thalassemia major, also known as Cooley's anemia, a potentially life-threatening form of thalassemia.
Getting tested for this trait can provide the following benefits:
Understanding the risk of having a child with this disease, especially if both partners are carriers
Identifying possible risk of anemia during pregnancy
Knowing whether your children are at risk of being carriers for future family planning
Prevent a misdiagnosis of iron deficiency anemia and the unnecessary prescription of iron supplements
Learn More: Genetic Predisposition: What It Is, What It Means for You
Mild Anemia: Symptoms of Beta Thalassemia Minor
Beta thalassemia minor symptoms may not be apparent in everyone affected by this condition. When they occur, symptoms of mild anemia are subtle and can often be overlooked. You may not know you have this disorder until your blood is tested.
When beta thalassemia minor results in mild hemolytic anemia (early breakdown of red blood cells), symptoms can include the following:
Being moody
Being more weak or tired than usual
Frequent headaches
Problems concentrating
If anemia becomes worse, the following symptoms may also develop:
Bluish color to the whites of your eyes
Feeling light-headed when moving from a sitting position to standing up
Pale appearance
Shortness of breath
Beta Thalassemia Minor vs. Beta Thalassemia Major
Thalassemia includes a group of blood disorders that affect hemoglobin production. Beta thalassemia typically falls into one of the following categories based on the severity of thalassemia:
Beta thalassemia minor (beta thalassemia minor trait): The affected person carries the trait but does not have the disease.
Beta thalassemia intermedia: The affected person has symptoms that fall between the minor and major categories, such as moderate anemia, and may require intermittent red blood cell transfusions.
Beta thalassemia major: The affected person needs lifelong medical care, transfusion of red blood cells, and chelation therapy to remove excess iron from their blood.
Do You Need Treatment With Beta Thalassemia Minor?
Most people do not need treatment with the beta thalassemia minor trait. The condition may cause a mild form of anemia, but it usually does not require medical treatment.
A person with beta thalassemia minor usually has a normal life expectancy. While hemoglobin production may be slightly decreased, delivering oxygen to the rest of your body is typically adequate to avoid complications.
In some cases, treatment may be required during physiological stress, pregnancy, or childhood when the condition can cause mild anemia. In these cases, consistent monitoring is required. Treatment may consist of the following:
Occasional blood transfusions (intravenous, or IV, administration of red blood cells)
Iron chelation therapy when needed to remove high levels of iron that occur with blood transfusions
Supplementation of folic acid (a form of supplemental vitamin B that promotes the development of red blood cells)
Beta Thalassemia Minor: Medicines and Supplements
Most people with beta thalassemia minor don't require medicines or supplements to treat their condition. If you are considering taking any type of medicine or supplements for beta thalassemia minor, it is important to consult with your healthcare provider before doing so.
Symptoms of beta thalassemia minor can sometimes lead to a misdiagnosis of iron deficiency anemia and iron supplements may be prescribed. However, taking iron supplements can increase your risk of iron overload, a common complication of thalassemia syndromes. Anyone with beta thalassemia minor should not take iron supplements.
While treatment usually isn't necessary, people with beta thalassemia minor may be prescribed folic acid. Folic acid can promote the development of red blood cells.
Research indicates that children with beta thalassemia minor may benefit from folic acid supplementation for three months. When symptoms occur, this treatment may help to increase hemoglobin levels, improve fatigue, and decrease bone pain and myalgia (muscle pain).
Clinical Classification of Beta Thalassemia
While beta thalassemia disorders are traditionally characterized as mild, intermediate, and major, a classification system based on their management with red blood cell transfusions may better reflect the clinical management and complications of each type.
This clinical classification system includes the following categories:
Mild
Very low anemia to low end of normal
Transfusions rarely required
Non-transfusion dependent thalassemia (NTDT)
Moderate anemia
Occasional to intermittent transfusions required
Transfusion dependent thalassemia (TDT)
Severe anemia
Lifelong transfusions required
Self-Care With Beta Thalassemia Minor
Self-care with beta thalassemia minor depends on the extent of your symptoms. Consult with your healthcare provider regarding your condition. Generally, living a healthy lifestyle, avoiding infections, and limiting iron intake are the best ways to support your well-being.
Common strategies for self-care with beta thalassemia minor may include the following:
Consult with a registered dietitian regarding adequate intake of calcium, vitamin D, vitamin E, vitamin C, and trace minerals (copper, zinc, and selenium).
Support a healthy diet with multivitamin supplementation without iron.
Take folic acid supplements as directed.
Avoid iron-fortified foods like cereals and consumption of red meat.
Limit alcohol consumption.
Do not smoke.
Exercise regularly to promote physical and mental well-being.
Find ways to reduce stress with activities like meditation, yoga, reading, or hobbies.
Foster supportive relationships with people who can help you manage the physical and emotional challenges you face with beta thalassemia minor.
Avoid infections with vaccines.
Summary
Beta thalassemia minor is a blood disease that is passed from parent to child. It lowers your blood's level of hemoglobin, which hinders the delivery of oxygen throughout your body.
This problem often occurs without symptoms. Many people learn they have it after getting the results of a blood test done for other reasons. This problem does not affect a normal life span.
Some people get mild anemia with it, Symptoms are often mild. Though rarely needed, treatment can involve taking folic acid, having blood transfusions, and handling iron levels in your blood.
Finding out whether you have this disorder can help you gauge your risk of passing it on. When two parents have the damaged gene, it raises the risk of a more severe form of thalassemia in their children.
