Beta-Thalassaemia
Beta-thalassaemia is an inherited blood disorder caused by reduced or absent production of beta-globin chains in hemoglobin. The disorder results in anemia, reduced oxygen transport, and abnormal red blood cell formation. Beta-thalassaemia is one of the most common hereditary blood disorders worldwide. :contentReference[oaicite:0]{index=0}
The disease is caused by mutations in the HBB gene located on chromosome 11. Severity varies depending on the type of genetic mutation inherited from the parents. :contentReference[oaicite:1]{index=1}
Overview
Hemoglobin is the oxygen-carrying protein found in red blood cells.
The disease mechanism can be represented as:
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Reduced beta-globin production leads to ineffective red blood cell formation and destruction of red blood cells. :contentReference[oaicite:3]{index=3}
Genetics
Beta-thalassaemia is inherited in an autosomal recessive manner.
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Mutations may either completely prevent beta-globin production or reduce its synthesis. :contentReference[oaicite:5]{index=5}
Beta-Zero Thalassaemia
No beta-globin chains are produced.
Beta-Plus Thalassaemia
Some beta-globin production still occurs. :contentReference[oaicite:6]{index=6}
Types
Beta-Thalassaemia Major
Also called Cooley's anemia, this is the most severe form.
Symptoms usually appear within the first two years of life and include:
- Severe anemia
- Pale skin
- Poor growth
- Enlarged spleen
- Bone deformities
- Fatigue
Patients generally require lifelong blood transfusions. :contentReference[oaicite:7]{index=7}
Beta-Thalassaemia Intermedia
This form causes moderate anemia and may not require regular transfusions. :contentReference[oaicite:8]{index=8}
Beta-Thalassaemia Minor
Also called thalassaemia trait, this is a mild carrier form with little or no symptoms. :contentReference[oaicite:9]{index=9}
Symptoms
Common symptoms include:
- Fatigue
- Weakness
- Pale skin
- Jaundice
- Delayed growth
- Enlarged liver or spleen
- Shortness of breath
Severe forms may cause skeletal abnormalities and heart complications. :contentReference[oaicite:10]{index=10}
Diagnosis
Doctors diagnose beta-thalassaemia using:
- Complete blood count (CBC)
- Blood smear
- Hemoglobin electrophoresis
- Iron studies
- DNA testing
Prenatal genetic testing may also be performed in high-risk families. :contentReference[oaicite:11]{index=11}
Treatment
Treatment depends on disease severity.
Common treatments include:
- Blood transfusions
- Iron chelation therapy
- Folic acid supplementation
- Bone marrow transplantation
- Gene therapy
Regular transfusions may lead to iron overload requiring chelation treatment. :contentReference[oaicite:12]{index=12}
Complications
Possible complications include:
- Iron overload
- Heart disease
- Liver damage
- Bone deformities
- Infections
- Delayed puberty
Untreated severe beta-thalassaemia may become life-threatening. :contentReference[oaicite:13]{index=13}
Epidemiology
Beta-thalassaemia is common in:
- Mediterranean countries
- Middle East
- South Asia
- Southeast Asia
- Africa
Carrier frequency is high in regions historically affected by malaria. :contentReference[oaicite:14]{index=14}
Prevention
Prevention methods include:
- Genetic counseling
- Carrier screening
- Prenatal diagnosis
- Family history evaluation
Early diagnosis improves treatment outcomes and quality of life. :contentReference[oaicite:15]{index=15}
Importance
Beta-thalassaemia is an important genetic and public health disorder because it affects blood formation, oxygen transport, and long-term health. Advances in transfusion therapy, genetics, and stem cell treatment have improved survival rates. :contentReference[oaicite:16]{index=16}