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Together is a new resource for anyone affected by pediatric cancer - patients and their parents, family members, and friends.
Learn MoreHemoglobin D trait is a change (mutation) in a gene that helps make hemoglobin in red blood cells. All red blood cells contain hemoglobin. Hemoglobin is a protein that carries oxygen from the lungs to all parts of the body.
People with normal hemoglobin have only one type, hemoglobin A. People with hemoglobin D trait have hemoglobin A and hemoglobin D in their red blood cells.
Most people with hemoglobin D trait have no signs or symptoms of illness. The trait normally does not cause any health problems.
People with hemoglobin D trait do not have hemoglobin D disease or hemoglobin SD disease. They cannot develop the conditions later in life. But they can pass the genes for the diseases on to their children.
Hemoglobin D trait is more common in people whose ancestors came from India or people of Asiatic Indian heritage. But it is possible for a person of any nationality or ancestry to have hemoglobin E trait.
A simple blood test can let you know if you have hemoglobin D trait. These tests are often done as part of routine newborn screening. Your doctor may suggest the test if someone in your family has hemoglobin D trait.
Hemoglobin D trait runs in families. Like eye color or hair color, the genes for hemoglobin D trait are inherited, or passed from parents to children.
Parents who have hemoglobin D trait can have a child with hemoglobin D disease, hemoglobin SD disease, or hemoglobin D/beta thalassemia disease.
Whether a child has the disease depends on genes from both parents. It is important to understand how hemoglobin C trait is passed on and how it can affect the health of your children and grandchildren.
If one parent has hemoglobin D trait and the other parent has normal hemoglobin:
With each pregnancy, there is a 50% (1 in 2) chance of having a child with hemoglobin D trait.
These are the possible outcomes with each pregnancy:
If both parents have hemoglobin D trait:
With each pregnancy, there is a 25% (1 in 4) chance of having a child with hemoglobin D disease.
These are the possible outcomes with each pregnancy:
If one parent has hemoglobin D trait and the other parent has sickle cell trait:
With each pregnancy, there is a 25% (1 in 4) chance of having a child with hemoglobin SD disease, a type of sickle cell disease.
People who have hemoglobin SD disease have red blood cells that contain both hemoglobin S and hemoglobin D. Hemoglobin SD disease is a lifelong illness that can cause serious health problems. People with the disease need medical treatment.
These are the possible outcomes with each pregnancy:
If one parent has hemoglobin D trait and the other parent has beta thalassemia trait:
With each pregnancy, there is a 25% (1 in 4) chance with each pregnancy of having a child with hemoglobin D/beta zero thalassemia (Dβ0) disease. Hemoglobin Dβ0 disease is a lifelong illness that can result in serious health problems.
These are the possible outcomes with each pregnancy:
To learn more about hemoglobin D trait, talk to your doctor or genetic counselor. Your care team can give more details about your trait status and that of your child.
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Reviewed: December 2023