The Thalassemia are inherited disorders of haemoglobin (Hb) synthesis. Their clinical severity varies widely, ranging from asymptomatic forms to severe or even fatal entities.
The word Thalassemia originates from a Greek word ‘THALASSA’ which means the sea, “haima” which means blood . This was first recognized among the Greek people living around the Mediterranean Sea.This is misleading because the condition can be found in any part of the world.
For every characteristic there is one gene which is inherited from the father and the other gene which is inherited from the mother. One of these pairs of genes determine the production of haemoglobin which carries oxygen and gives blood the red colour. The haemoglobin is made up of two alpha globin chains and two beta globin chains with a haem particle in the middle.
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BETA THALASSEMIA MINOR : If one of the genes responsible for the production of beta globin is defective it produces beta-thalassemia trait, also called beta-thalassemia minor. As this is asymptomatic it remains unrecognised in a family for a number of generations. The beta thalassemia trait individuals are normal healthy people, leading a normal active life.
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BETA THALASSEMIA MAJOR : When a beta thalassemia trait (in whom only one gene is defective) marries another beta thalassemia trait then a child can be born with two defective genes for the production of beta globin chains.
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BETA THALASSEMIA INTERMEDIA is a condition intermediate between the major and minor forms. Affected individuals can often manage a normal life but may need occasional transfusions e.g. at times of illness or pregnancy, depending on the severity of their anemia
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In combination with other hemoglobinopathie
Thalassemia can co-exist with other hemoglobinopathies. The most common of these are :
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hemoglobin E/thalassemia: common in Cambodia, Thailand, and parts of India; clinically similar to β thalassemia major or thalassemia intermedia.
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hemoglobin S/thalassemia, common in African and Mediterranean populations; clinically similar to sickle cell anemia, with the additional feature of splenomegaly
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hemoglobin C/thalassemia: common in Mediterranean and African populations, hemoglobin C/βo thalassemia causes a moderately severe hemolytic anemia with splenomegaly; hemoglobin C/β+ Thalassemia produces a milder disease