Sickle cell disease (SCD) is a common disorder of the red blood cells, or hemoglobin. The name comes from the shape of the red blood cells, which become shaped like a C or a sickle.
What is Sickle Cell Trait (SCT)?
Sickle cell trait (SCT) is a type of hemoglobinopathy or an inherited blood disorder. It affects between 1 and 3 million Americans, according to the American Society of Hematology.
A person with SCT has inherited only one copy of the sickle cell gene from a parent. A person with sickle cell disease (SCD) has two copies of the gene, one from each parent.
SCT can never turn into SCD. Because a person with SCT has only one copy of the gene, they will never develop SCD. Instead, they are considered a carrier for the disease. That means they can pass the gene for the disease on to their children. A simple blood test from your doctor can determine if you are a carrier and at risk of passing along SCT.
Those who are at increased risk of having SCT include people of:
- African,
- Hispanic,
- South Asian,
- Southern European, or
- Middle Eastern descent.
How is SCT Inherited?
- If both parents have SCT, there is a 50% (or 1 in 2) chance that any child of theirs also will have SCT, if the child inherits the sickle cell gene from one of the parents. Such children will not have symptoms of SCD, but they will have SCT and can pass SCT on to their children.
- If both parents have SCT, there is a 25% (or 1 in 4) chance that any child of theirs will have SCD. There is the same 25% (or 1 in 4) chance that the child will not have SCD or SCT.
How can SCT impact a person's health?
Although rare, people with SCT can develop symptoms of SCD, such as pain crises, under extreme conditions. These conditions include:
- Increased pressure in the atmosphere, such as with scuba diving,
- Low oxygen levels, which can occur while performing strenuous physical activity,
- High altitudes,
- Dehydration,
- Athletes with SCT need to take precautions when performing. Staying hydrated is extremely important.
Some conditions linked to SCT, include:
- Reduced blood supply to the spleen,
- Muscle breakdown (rhabdomyolysis),
- Kidney damage and chronic kidney disease,
- Bleeding (hyphema) and increased pressure in the eye (glaucoma) following eye injuries, and
- Blood in the urine (hematuria).
What are other kinds of hemoglobinopathy traits?
Hemoglobinopathies are a group of disorders passed down through families in which there is abnormal production or structure of the hemoglobin molecule. The most commonly known hemoglobinopathy is SCD. Besides SCT, there are two kinds of thalassemia trait: alpha thalassemia trait and beta thalassemia trait. Like SCT, people with alpha or beta thalassemia traits have inherited one copy of the thalassemia gene and do not have a disease, and the trait cannot become disease. Both types of thalassemia trait can cause the size of the red blood cells to be smaller than normal, which looks like iron deficiency anemia, but it does not require treatment.
What do I need to know about SCT and sports?
People with SCT can safely participate in all sports provided they take a few general precautions, such as:
- Drinking enough water,
- Taking breaks when needed, and
- Not overdoing it, especially when starting a new exercise program.
The conditions that increase the risk of exercise-related illness for athletes with SCT appear to be the same as those that increase the risk for athletes who do not have SCT and include:
- Significant and sudden increase in exercise intensity,
- Failure to adjust gradually to new environmental conditions like higher altitude, increased heat, or higher humidity,
- Exercising when ill or dehydrated (lack of fluids), and
- Drug, alcohol, or stimulant use.
What does the Maryland Department of Health's Sickle Cell Disease Follow-Up Program do?
The program follows newborns, children, and young adults with SCD up to age 18, providing them and their families information about sickle cell disease (SCD) and other hemoglobin disorders, what to expect from your doctor and specialist, guides to living with SCD, and other information pertaining to daycare, school, sports, transitioning to an adult doctor, web resources and organizations of interest to persons with SCD.
- Self-Referral- The SCD Follow-Up Program provides support and resources to babies born with SCD in Maryland. However, families with children with SCD, who were born in other states are welcome to enroll. Please complete this form and Program Staff will contact you.
Click here to complete the self-referral form.
