Hemochromatosis Gene Test (HFE Test)
Hemochromatosis gene (HFE) testing is a blood test used to check for hereditary hemochromatosis, an inherited disorder that causes the body to absorb too much iron. The iron then builds up in the blood, liver, heart, pancreas, joints, skin, and other organs.
In its early stages, hemochromatosis can cause joint and belly pain, weakness, lack of energy, and weight loss. It can also cause scarring of the liver (cirrhosis), darkening of the skin, diabetes, infertility, heart failure, irregular heartbeats (arrhythmia), and arthritis. But many people do not have symptoms in the early stages.
In men, hereditary hemochromatosis is usually found between the ages of 40 and 60. In women, it is not usually found until after menopause because, until that time, women regularly lose blood and iron during their monthly periods.
Why It Is Done
HFE testing is used to find out if a person has an increased chance of having hemochromatosis. It is often recommended for people who have a close family member—parent, brother, sister, or child—with this disease.
HFE testing locates and identifies common mutations in the HFE gene. It is used to find out if a person has an increased chance of having hemochromatosis. You may decide to have HFE testing:
- If other people in your family have hemochromatosis and you want to see if you carry a mutation and might pass the disease on to your children. Information from screening can help you make decisions about your health care.
- If two separate blood tests, which include a ferritin level and transferrin saturation, are done and they show that you have high iron levels in your blood (iron overload). More than half of people with iron overload have HFE gene mutations.
- To find out whether you have hemochromatosis before you develop related problems, such as liver disease. Early treatment can help prevent later problems. Treatment can be as simple as routinely removing blood, in the same way as blood is removed when you donate blood. This brings iron levels down.
How To Prepare
Generally, no special preparation is required before having a hemochromatosis gene test.
Genetic test results often have ethical, legal, or social implications. You may want to talk to a genetic counselor before making a decision about testing. Genetic counselors are trained to explain the test and its results clearly. A genetic counselor can help you make well-informed decisions.
Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?) .
How It Is Done
The health professional taking a sample of your blood will:
- Wrap an elastic band around your upper arm to stop the flow of blood. This makes the veins below the band larger so it is easier to put a needle into the vein.
- Clean the needle site with alcohol.
- Put the needle into the vein. More than one needle stick may be needed.
- Attach a tube to the needle to fill it with blood.
- Remove the band from your arm when enough blood is collected.
- Put a gauze pad or cotton ball over the needle site as the needle is removed.
- Put pressure on the site and then put on a bandage.
How It Feels
The blood sample is taken from a vein in your arm. An elastic band is wrapped around your upper arm. It may feel tight. You may feel nothing at all from the needle, or you may feel a quick sting or pinch.
You may worry or feel nervous before you have the test or while you are waiting for the results.
There is very little chance of a problem from having blood sample taken from a vein.
- You may get a small bruise at the site. You can lower the chance of bruising by keeping pressure on the site for several minutes.
- In rare cases, the vein may become swollen after the blood sample is taken. This problem is called phlebitis. A warm compress can be used several times a day to treat this.
- Ongoing bleeding can be a problem for people with bleeding disorders. Aspirin, warfarin (Coumadin), and other blood-thinning medicines can make bleeding more likely. If you have bleeding or clotting problems, or if you take blood-thinning medicine, tell your doctor before your blood sample is taken.
Hemochromatosis gene (HFE) testing is a blood test used to check for hereditary hemochromatosis, a disorder that is passed from a parent to a child (inherited) and causes the body to absorb too much iron. This HFE gene test is usually not used to check for other, less common causes of inherited hemochromatosis.
No mutations are found in the HFE gene. Normal results are called negative.
Mutations are found in the HFE gene test. Abnormal results are called positive.
An abnormal test result does not mean that you have hemochromatosis or that you will have hemochromatosis. It means that you have a mutation in the HFE gene. Ask your doctor or a genetic counselor to help you understand your test results.
What Affects the Test
The results of a hemochromatosis gene test may not be accurate if you have had a blood transfusion done within a week of the test.
What To Think About
- If you are thinking about having genetic testing, talk with your doctor about the benefits as well as the possibility of insurance, employment, or other discrimination based on test results. An HFE test result is private information.
- The information obtained from an HFE test can have a big impact on your life. Genetic counselors are trained to help you understand your chance for having a child with an inherited (genetic) disease. A genetic counselor can help you make well-informed decisions. Ask to have genetic counseling before making a decision about HFE testing.
- HFE testing is not able to predict whether you will have hemochromatosis. Although the test locates the most common HFE mutations, there may be other HFE mutations that the test does not find. You may have HFE mutations and not have the diseases or you may have symptoms of the disease but gene testing is does not find any mutations.
- HFE gene testing may identify the cause of high iron levels and eliminate the need for other tests, such as a liver biopsy.
- Iron and ferritin levels may also be checked at the same time as a hemochromatosis gene test. For more information, see the medical tests Iron and Ferritin.
Other Works Consulted
- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.
- Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
- National Human Genome Research Institute (2008). Learning about hereditary hemochromatosis. Available online: http://www.genome.gov/page.cfm?pageID=10001214.
- Qaseem A, et al. (2005). Screening for hereditary hemochromatosis: A clinical practice guideline from the American College of Physicians. Annals of Internal Medicine, 143(7): 517–521.
|Author||Robin Parks, MS|
|Editor||Kathleen M. Ariss, MS|
|Associate Editor||Tracy Landauer|
|Primary Medical Reviewer||E. Gregory Thompson, MD - Internal Medicine|
|Specialist Medical Reviewer||Brian Leber, MDCM, FRCPC - Hematology|
|Last Updated||April 20, 2009|