Hemoglobin E Trait

Hemoglobin E trait is a hereditary blood disorder, which means it is inherited from your parents.

Facts about hemoglobin E trait

Mother holding infant.

Hemoglobin E trait is rare. It occurs most frequently among people with a Thai, Cambodian, Vietnamese, or Laotian background. It can also occur in people of Turkish, Asiatic Indian, Chinese, and Filipino descent.

Types of hemoglobin E trait

If you inherited the hemoglobin E mutation from just one of your parents, you typically won't have any symptoms, but you are a carrier of the disease. That means you run the risk of having children with more serious illnesses related to hemoglobin E.

If you inherited hemoglobin E from both parents, however, it can cause additional complications, such as:

  • Hemoglobin E disease. Hemoglobin E disease causes a slight mutation in the hemoglobin beta, or HBB, gene. The result of this mutation is that red blood cells may be smaller than normal and have an irregular shape.

  • Hemoglobin E/thalassemia. In this variation of the disease, the hemoglobin E causes anemia and associated symptoms that can lead to more severe complications.

  • Hemoglobin sickle E disease. This is a milder form of the more commonly known sickle cell anemia.  


Many people have no symptoms. Those with more severe hemoglobin E-related disorders may experience mild thalassemia, or anemia-like symptoms, but even these are rare. When they do occur, they may include:

  • Fatigue

  • Growth failure

  • Shortness of breath

  • Jaundice, or a yellowing of the skin


Hemoglobin E trait is typically discovered in infants during newborn screenings. The specific test is known as a mean corpuscular volume test and is part of the complete blood count test. The testing might also include elements such as hemoglobin electrophoresis or iron studies. A genetic test of the HBB gene may also be performed.

If you are a known carrier of hemoglobin E trait, hemoglobin testing is recommended if you want to have children. If your partner is also a carrier, you risk having a child with hemoglobin E disease, hemoglobin E/thalassemia, or hemoglobin sickle E disease.


In most cases, hemoglobin E disease is benign, and no treatment is needed. Sometimes a doctor might prescribe folic acid supplements to help with red blood cell count and the symptoms of anemia.


Because hemoglobin E trait and the related diseases are hereditary, the only thing that you can do to avoid the spread of it is not to have children with someone who is also a carrier of hemoglobin E. Of course, this is a highly personal decision that you'll want to discuss with your partner and health care provider.

Managing hemoglobin E trait

Most people with hemoglobin E trait and hemoglobin E disease will live a healthy, normal life. Other than appropriate family planning, little management of the condition is needed.