Alpha Thalassemia

  • Alpha thalassemia is a hemoglobinopathy that is characterized by decreased synthesis of the alpha-globin chain and a consequent increase in the amount of the beta chain.
  • The excess beta chains will precipitate in the cell and damage the cell membrane, causing hemolysis.
  • Alpha thalassemia is caused by deletion of the genes responsible for Alpha chain synthesis.
  • It can be inherited in an autosomal dominant or autosomal recessive manner and different patients will present with different clinical pictures.
  • The oxygen-carrying capacity of the blood is reduced
  • As stated above, in alpha thalassemias, the synthesis of the alpha chain of globin is reduced. Since both the fetal and adult forms of haemoglobin contain the alpha chain, they are both affected by this.
  • In the fetus, instead of two alpha and two gamma chains, four gamma chains will be produced instead. This is known as Bart's Hemoglobin(Hb Bart's). Fetuses with alpha thalassemia are born with generalized oedema knows as Hydrops fetalis.
  • In adults, instead of two alpha and two beta chains, four beta chains will be formed instead. This is known as Hemoglobin H(HbH). In mild forms of thalassemia, the patient will have anaemia.

Beta Thalassemia

  • Beta thalassemia is a hemoglobinopathy that is characterized by a decreased synthesis of the beta-globin chain and a consequent

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