This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
Beta-thalassemia is a blood disorder that reduces the body’s production of hemoglobin. Low levels of hemoglobin lead to a shortage of mature red blood cells and a lack of oxygen in the body. People with beta-thalassemia have anemia, which can cause paleness, weakness, fatigue, and more serious complications. There are two main forms of beta-thalassemia, classified based on the severity of symptoms:
Beta-thalassemia is caused by mutations in the HBB gene and is typically inherited in an autosomal recessive manner. This means that people with thalassemia major or thalassemia intermedia have a mutation in both of their copies of the HBB gene.
People who have only one HBB gene mutation (carriers) typically are said to have thalassemia minor (or trait) and usually do not have symptoms, but may have some symptoms of anemia. In some cases, anemia is worsened if there is a nutritional deficiency such as with iron, folic acid or vitamin B12.
Very rarely, the inheritance of beta-thalassemia may be dominant. In this case, a person has only one mutated HBB gene, but has signs and symptoms of beta-thalassemia major or beta-thalassemia intermedia.
The exact treatment plan for beta-thalassemia depends on the symptoms and severity in each person.
For more information, visit GARD.