Thalassemia

    

Thalassemia is a blood disorder passed down through families (inherited) in which the body makes an abnormal form of hemoglobin. Hemoglobin is the protein in red blood cells that carries oxygen. The disorder results in large numbers of red blood cells being destroyed, which leads to anemia.

Causes

 

Hemoglobin is made of 2 proteins:

Alpha globin

Beta globin

 

Thalassemia occurs when there is a defect in a gene that helps control production of 1 of these proteins.

There are 2 main types of thalassemia:

Alpha thalassemia occurs when a gene or genes related to the alpha globin protein are missing or changed (mutated).

Beta thalassemia occurs when similar gene defects affect production of the beta globin protein.

Alpha thalassemias occur most often in people from Southeast Asia, the Middle East, China, and in those of African descent.

Beta thalassemias occur most often in people of Mediterranean origin. To a lesser extent, Chinese, other Asians, and African Americans can be affected.

There are many forms of thalassemia. Each type has many different subtypes. Both alpha and beta thalassemia include the following 2 forms:

Thalassemia major

Thalassemia minor

You must inherit the gene defect from both parents to develop thalassemia major.

Thalassemia minor occurs if you receive the faulty gene from only 1 parent. People with this form of the disorder are carriers of the disease. Most of the time, they do not have symptoms.

Beta thalassemia major is also called Cooley anemia.

Risk factors for thalassemia include:

Asian, Chinese, Mediterranean, or African American ethnicity

Family history of the disorder