let's recode the building blocks
Beta-thalassemia is a potentially severe, genetic blood disease that is characterized by a reduced or no production of β-globin, a component of an oxygen-carrying protein called hemoglobin. β-thalassemia is caused by mutations in the beta-globin (HBB) gene. Individuals with β-thalassemia minor have a mutation in one HBB gene, while individuals with the intermediate and major forms have mutations in both HBB genes.1 Because healthy red blood cells are not formed, β-thalassemia can eventually lead to anemia, fatigue and other issues, as it impacts the delivery of oxygen in an individual’s blood cells. Mild forms of β-thalassemia may not need treatment.
The most severe type of β-thalassemia, transfusion-dependent β-thalassemia (TDT), is a type of β-thalassemia characterized by severe anemia and a lifelong dependence on red blood cell transfusions that can lead to iron overload. Because of repeated blood transfusions, individuals with transfusion-dependent β-thalassemia may develop iron overload. The accumulation of iron can be toxic and lead to progressive multi-organ damage. Effective management of iron overload requires lifelong iron chelation therapy.2 3 4
What are the symptoms?
Red blood cells carry oxygen to all cells and tissues of the body. Since oxygen is a fuel that all cells require to function, when there are not enough healthy red blood cells, there is also not enough oxygen delivered to all the other cells of the body. This condition is called anemia, and patients (person) may feel tired, weak or short of breath.5 If left untreated, severe anemia can damage organs and potentially lead to death.6
What causes it?
β-thalassemia is caused by genetic mutations in the gene involved in making a protein called β-globin, which is a key component of a larger protein called adult hemoglobin, that is responsible for carrying oxygen to all parts of the body.
How is it diagnosed
People with moderate and severe forms of thalassemia usually find out about their condition in childhood, as they have symptoms of severe anemia early in life. Because thalassemias are inherited, the condition usually runs in families. Some people find out about their thalassemia because they have relatives with a similar condition.7
Given that β-thalassemia occurs more frequently in individuals from certain parts of the world — Mediterranean countries, like Greece and Turkey, central Asia, Africa and the Middle East — these individuals are more likely to have β-thalassemia.8 If you have anemia and you also have family members from these areas, your doctor might test your blood further to find out if you have β-thalassemia. Newborn screenings are also common for people who have families originating from these areas.
What is the effect of TDT?
People with TDT require lifelong supportive care with regular blood transfusions — typically given every two to five weeks — to lessen the symptoms of anemia. Without regular blood transfusions, people with TDT cannot survive.
Despite the availability of supportive care, many people with TDT experience serious complications and organ damage due to iron overload. By eliminating or reducing the need for blood transfusions, the long-term complications associated with TDT may be reduced.9
How common is beta-thalassemia?
β-thalassemia is estimated to affect approximately 1 in 100,000 individuals in the general population. The disorder is particularly prevalent in the Mediterranean, Middle East, Africa, central Asia, the Indian subcontinent and the Far East. Individuals in other parts of the world whose families are from these regions carry a greater risk of having β-thalassemia.
Find out more.
You can find more information about β-thalassemia by visiting patient resources.
1https://rarediseases.org/rare-diseases/thalassemia-major/ 2Cappellini MD, Cohen A, Porter J, Taher A, Viprakasit V, eds.Guidelines for the management of transfusion-dependent thalassaemia[TDT]. 3rd ed. Nicosia, Cyprus: Thalassaemia International Federation; 2014. 3K. Bayanzay. Reducing the iron burden and improving survival in transfusion-dependent thalassemia patients: current perspectives. Journal of Blood Medicine. 6 August 2016: 7 159-169 4Musallam KM, Angastiniotis M, Eleftheriou A, Porter JB. Cross-talk between available guidelines for the management of patients with beta-thalassemia major. Acta Haematol. 2013;130(2):64-73. 5Hemoglobin is an iron-rich protein that helps red blood cells carry oxygen from the lungs to the rest of the body. If you have anemia, your body does not get enough oxygen-rich blood. This can cause you to feel tired or weak. You may also have shortness of breath, dizziness, headaches, or an irregular heartbeat. https://www.nhlbi.nih.gov/health-topics/anemia 6https://www.cdc.gov/ncbddd/thalassemia/facts.html 7https://www.cdc.gov/ncbddd/thalassemia/facts.html 8https://www.cdc.gov/ncbddd/thalassemia/facts.html 9 Galanello R., Origa R. Beta-thalassemia. Orphanet J Rare Dis. 2010;5:11. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2893117/Accessed March 2019.