Newborn Screening Information for Families: Trait - Minnesota Dept. of Health

Newborn Screening Information for Families:
Hemoglobin and Sickle Cell Trait

smiling family lying in the grass


On this page:
What is Trait?
Hemoglobin Trait Communication
Why It Is Important To Know If You Have A Hemoglobin Trait
Educational Flyers
FAQ
Additional Information
Contact Information


What is Trait?

Trait is when a person has some normal hemoglobin and some abnormal hemoglobin. Hemoglobin is part of the red blood cells and its job is to carry oxygen throughout the body. One type of testing done in newborn screening is to look for a group of disorders called hemoglobinopathies. Hemoglobinopathies are inherited disorders that affect the structure of the hemoglobin. You may be familiar with the most common hemoglobinopathy, sickle cell disease. However, unlike sickle cell disease, an individual with trait is expected to be healthy and could live their whole life without knowing they have trait. While sickle cell trait is the most common trait, there are many other traits as well (such as C trait, E trait, or D trait). When any trait is inherited along with normal hemoglobin, it is expected that a person would be healthy.


Hemoglobin Trait Communication

If a baby is found to have a trait through newborn screening, the mother of the baby will receive a packet of information in the mail about the specific trait the baby was found to have.

We will directly contact the baby's doctor or clinic listed on the newborn screening card to confirm they have seen the baby and send them the results of the newborn screen. This is one of the reasons it is important for hospitals and birth providers to get the name of a baby's doctor or clinic so that the baby newborn screening results can be promptly sent to them.

Parents of babies with a trait should:

  • Have a discussion with their baby's doctor about the result, their next steps, and the importance of the result for themselves, their child, and their family.
  • Make sure to have their baby retested for the trait at six months of age to confirm the result.
  • Keep a record of the test results and the packet of information from the newborn screening program for future reference.

Illustration of the hemoglobin trait communication process

Why It Is Important To Know If You Have A Hemoglobin Trait

Hemoglobin trait is inherited from your parents, like hair or eye color. If one parent has a hemoglobin trait, there is a 50% (1 in 2) chance with each pregnancy of having a child with a hemoglobin trait.

If both parents have a hemoglobin trait, there is a 25% (1 in 4) chance with each pregnancy of having a child with a serious hemoglobin disease, like sickle cell disease.

Below is one example of how two parents with trait can have a child with disease: Pedigree of two parents each with sickle cell trait that shows the chance with each pregnancy of having a child with sickle cell trait.

With each pregnancy, this couple has a 25% (1 in 4) chance of having a child with sickle cell disease, a 50% (2 in 4) chance of having a child with sickle cell trait, and a 25% (1 in 4) chance of having a child with no trait or disease.


Educational Flyers

Sickle Cell Trait (PDF)
Hemoglobin C Trait (PDF)
Hemoglobin D Trait (PDF)
Hemoglobin E Trait (PDF)
Hemoglobin Variant Trait (PDF)


Frequently Asked Questions

A: If you have sickle cell trait, you have inherited the gene for sickle cell disease. Sickle cell trait does not turn into sickle cell disease. If someone has sickle cell trait and their partner also has sickle cell trait, they may have a child with sickle cell disease.
A: Sickle cell trait is the most common hemoglobin trait. Other more common hemoglobin traits are C trait, D trait, E trait. Like sickle cell trait, these traits do not turn into disease. If someone has a hemoglobin trait and their partner also has a hemoglobin trait, they may have a child with a hemoglobin disease.
A: A person who has trait has inherited one normal copy of this gene, and one abnormal copy of this gene. That means they have some normal red blood cells. A person with a trait usually does not know they have a trait unless they are tested. Trait does not cause any symptoms and requires no medication for their trait. The greatest risk for a person with a trait is their risk to have a child with a hemoglobin disease.
A person with a hemoglobin disease has inherited two genes that affect their red blood cells. People with a hemoglobin disease require special health care for their entire lifetime to manage their disease.
A: The most important reason to know if you have a trait is for family planning. Individuals who have a trait are at a higher risk to have a child with a hemoglobin disease, like sickle cell disease. Also, there are some rare health problems that can happen in people with a trait, so it can be important for doctors to discuss trait status with their patients every year. To learn about your individual risk, talk with a healthcare professional or a genetic counselor.
A: Babies are tested at birth for many different hemoglobin disorders, including sickle cell disease. The way this testing is done it shows babies who have a trait, even though that is not what is being looked for. Since trait runs in families, it is important to let the baby’s caregiver and doctor know this was found.
A: People from any race or ethnicity can have a hemoglobin trait. Certain types of hemoglobin trait are more common in people of certain ethnicities. For example, sickle cell trait is most common in individuals of from sub-Saharan African descent, but can also be found in people from South America, Caribbean, Central America, Italy, Greece, Turkey, Saudi Arabia and India. Other traits such as hemoglobin E trait are most common in individuals of Southeast Asian descent. Hemoglobin D trait is most common in people of East Indian descent.
A: The only way to know if you have a hemoglobin trait is to be tested. A simple blood test called a hemoglobin electrophoresis can tell you if you have a hemoglobin trait.

Additional Information

Center for Disease Control: Hemoglobinopathies Monitoring
Region 4 Midwest Genetics Collaboritive: Hemoglobinopathies
Baby's First Test: Hemoglobinopathies
American Society of Hematology: Sickle-Cell/
American Society of Hematology: State of Sickle Cell Disease 2016 Report (PDF)


Contact Information

Questions? Call our hemoglobin trait educator at 651-201-5515 or through email at health.newbornscreening@state.mn.us