Thalassemia can be passed to children

Donya Betancourt, Pediatrician, drdonya@hotmail.com

Thalassemia is an inherited blood disorder that affects the production of normal hemoglobin -- a type of protein in red blood cells that carries oxygen to the tissues of the body -- resulting in anemia. The severity and type of anemia depends upon the number of genes that are affected.

There are two kinds of thalassemias, alpha thalassemia and beta thalassemia.

Thalassemia occurs in two forms:

1. Thalassemia trait or thalassemia minor which is not a disease.

2. Thalassemia major is a disease.

Since thalassemia is inherited, a person can pass it on to one's child. If one parent has thalassemia trait and the other parent has the normal type of hemoglobin (A), there is a 50 percent chance with EACH pregnancy that the baby will be born with thalassemia trait.

Look at the diagram below (A represents normal hemoglobin and T represents thalassemia): Father AT, Mother AA, Children AA AA AT AT. It means that each child has a 50 percent chance of thalassemia trait.

In the normal adult, there are three kinds of hemoglobin in the body.

1. Hemoglobin A, which is composed of two alpha and two beta globins, and is the most prevalent, comprising about 95 percent of all hemoglobin.

2. Hemoglobin A2, is composed of two alpha and two delta globins, comprising 2 percent to 3.5 percent of hemoglobin.

3. Hemoglobin F, composed of two alpha and two gamma globins, comprises less than 2 percent of hemoglobin.

What is thalassemia major?

Thalassemia major occurs when a person inherits two thalassemia genes, one from each parent.

Father AT, Mother AT, Children AA AT TT AT. It means each child has 1 in 3 possibility outcome: 25 percent chance of normal hemoglobin, 50 percent chance of thalassemia trait, 25 percent chance of thalassemia major

The baby with thalassemia major appears normal at birth. Toward the end of the first year energy diminishes. The skin becomes pale, certain bones of the face may become prominent, and growth is slower than normal. Anemia is found and treatment with iron fails. Blood transfusions are required and are generally continued throughout life. Although there is treatment, it is not satisfactory and there is NO cure. Life span is reduced.

Thalassemia major does not cause mental retardation, but is a severe physical handicap.

There is a simple and accurate blood test for thalassemia. This test is not done routinely and must be requested.

Why is it important to know that you have thalassemia trait or not?

If you have thalassemia trait, you may have a mild anemia. This anemia might be mistaken for other kinds of anemia, especially iron deficiency anemia. Iron medication is not necessary and may even be harmful unless it has been established by specific tests that you are deficient in iron.

If you and your partner have thalassemia trait, you are at risk of having children with thalassemia major, a serious disease without satisfactory treatment. At the present time, the principal treatment for children with thalassemia major is regular blood transfusions.

If you have thalassemia trait, you need not be concerned for your own health. However, you may be at risk for having a child with thalassemia major.

If one of the parents is tested and proved to have the normal hemoglobin, then no child born to the two of you can have thalassemia major. However, if your partner does have thalassemia trait, you are at risk of having a child with thalassemia major. Your physician can discuss the options available to you.

Even if you already have children who do not have thalassemia major, you might still consider a test for your partner. As usual an ounce of prevention is far better than a pound of treatment.