Thalassemia (Mediterranean Anemia)

What Is Thalassemia?

It is a hereditary blood disease that is seen most often in Mediterranean countries but has spread all over the world because of migration, and that can easily be prevented with education and screening tests.

How Does Thalassemia Occur?

Thalassemia results from a defect in the production of hemoglobin. Hemoglobin is a molecule that carries the oxygen it takes from the lungs to the tissues and regulates it. It is found inside the erythrocytes (red blood cells) in the blood. It has two parts, "heme" and "globin". The globin part contains two chains called alpha and beta. The production of these chains is controlled by genes. The absence or insufficiency of production of one of the chains causes thalassemia. A deficiency in the alpha chain causes alpha thalassemia, and a deficiency in the beta chain causes beta thalassemia.

Beta Thalassemia has three clinically different forms:

1. Thalassemia carrier state (Thalassemia minor)
2. Thalassemia intermedia
3. Thalassemia major

In thalassemia carriers, the person is healthy apart from signs of mild anemia, and only carries the thalassemia gene. However, when two carriers marry, the child to be born has a 25% chance of being sick, a 50% chance of being a carrier, and a 25% chance of being normal. Marriages between relatives increase the probability of two defective genes coming together, and thus the probability of their children being sick. For prevention, marriages between relatives must be prevented through public education. Also, especially in high-risk regions, people should undergo a screening test for thalassemia carrier status with hemoglobin analysis before marriage, and it should be determined whether or not they are carriers. Beta thalassemia carrier status is detected by hemoglobin analysis; for alpha thalassemia carrier status, a definitive result is given by alpha-globin DNA analysis. There is no obstacle to two thalassemia carriers marrying. However, when these couples plan to have a child, they should apply to a genetic diagnosis center, find out through prenatal diagnosis whether the baby will be affected, and receive genetic counseling.