Definition

Thalassemia is an inherited disorder. It leads to the decreased production and increased destruction of red blood cells. Hemoglobin in the red blood cells carry oxygen for all organs in the body. The loss of red blood cells results in low hemoglobin. This leads to anemia . The decreased oxygen will impair the ability to maintain normal functions.

Hemoglobin

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Hemoglobin is made of two separate amino acid chains. They are alpha and beta. Thalassemias are categorized by the specific chain and number of genes affected:

Alpha thalassemia—the alpha chain is affected

• Silent carrier—one gene affected
• Thalassemia trait—two genes affected
• Hemoglobin H disease—three genes affected
• Alpha hydrops fetalis—four genes affected, most severe form, results in fetal or newborn death

Beta thalassemia—the beta chain is affected

• Thalassemia minor—one abnormal gene
• Thalassemia major (Cooley's anemia)—two abnormal genes