Hemoglobin D Trait



What is Hemoglobin?

Hemoglobin is the main ingredient in red blood cells. Hemoglobin helps red blood cells carry oxygen from the lungs to other parts of the body. Normal red blood cells have hemoglobin A. People with hemoglobin D trait have red blood cells that have normal hemoglobin A and an abnormal hemoglobin. The abnormal hemoglobin is called hemoglobin D. People with hemoglobin D trait have slightly more hemoglobin A than hemoglobin D. People with Hemoglobin D trait do not have health problems related to having the trait.

People with hemoglobin D trait do not have Hemoglobin D disease or sickle cell disease. They cannot develop these diseases later in life. They can pass hemoglobin D trait to their children.


How is Hemoglobin D Trait Inherited?

Hemoglobin D trait is inherited from one's parents, like hair color or eye color. If one parent has hemoglobin D trait and the other parent has normal hemoglobin, there is a 50 percent (1 in 2) chance with each pregnancy of having a child who has hemoglobin D trait. These are the possible outcomes with each pregnancy.

Why is it Important to Know if I Have Hemoglobin D Trait?

Parents who have hemoglobin D trait can have a child with Hemoglobin D disease, Hemoglobin SD disease or Hemoglobin D/Beta Thalassemia Disease. This is why it is important to understand how hemoglobin D trait is passed on, and how it can affect the health of your children and grandchildren.


Hemoglobin SD disease

Hemoglobin SD disease is a type of sickle cell disease. People with Hemoglobin SD disease have red blood cells that contain both sickle hemoglobin (hemoglobin S) and hemoglobin D. The type of Hemoglobin D usually determines the severity of the disease. Hemoglobin D-Los Angeles (also known as D-Punjab) together with sickle hemoglobin creates a type of sickle cell disease that can cause significant health problems.


How is Hemoglobin SD Disease Inherited?

People inherit Hemoglobin SD disease from their parents. If one parent has hemoglobin D trait and the other person has sickle cell trait, there is a 25 percent (1 in 4) chance with each pregnancy of having a child with sickle cell (SD) disease. Sickle cell disease is a lifelong illness that can result in health problems. These are the possible outcomes with each pregnancy.

Hemoglobin D disease

People with hemoglobin D trait can also have a child with hemoglobin D disease. Hemoglobin D disease is not a form of sickle cell disease. People who have hemoglobin D disease have red blood cells that contain mostly hemoglobin D. Too much hemoglobin D can reduce the number and size of red blood cells in your body, causing mild anemia. Hemoglobin D disease is rare and usually does not cause serious health problems.

If both parents have hemoglobin D trait, there is a chance of having a child with hemoglobin D disease. These are the possible outcomes with each pregnancy.

How is Hemoglobin D/Beta ZeroThalassemia Disease Inherited?

People inherit Hemoglobin D from their parents. If one parent has hemoglobin D trait and the other parent has beta zero thalassemia trait, there is a 25 percent (1 in 4) chance with each pregnancy of having a child with Hemoglobin D/Beta ZeroThalassemia (Dβ0) disease. Hemoglobin Dβ0 disease is a lifelong illness that can result in serious health problems. These are the possible outcomes with each pregnancy.

Review – How Hemoglobin D Disease, Hemoglobin SD Disease and Hemoglobin D/Beta Zero Thalassemia Disease are Inherited

If one parent has Hemoglobin D trait and the other parent has sickle cell trait, there is a 25 percent (1 in 4) chance with each pregnancy of having a child with sickle cell disease (Hemoglobin SD disease). Some types of Hemoglobin SD disease can cause health problems.

If both parents have hemoglobin D trait, there is a 25 percent (1 in 4) chance with each pregnancy of having a child with hemoglobin D disease. Hemoglobin D disease usually does not cause serious health problems from the disease.

If one parent has Hemoglobin D trait and the other parent has beta thalassemia trait, there is a 25 percent (1 in 4) chance with each pregnancy of having a child with hemoglobin D/Beta Zero Thalassemia disease. Hemoglobin D/Beta Zero Thalassemia disease can cause serious health problems.

The only way to know if you have hemoglobin D trait is to have a simple blood test.

Talk to your physician about genetic testing and counseling if you or a member of your family member has Hemoglobin D trait.