Hemochromatosis Gene Test (HFE Test)
Hemochromatosis Gene Test (HFE Test)Skip to the navigationTest OverviewHemochromatosis
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
at ages 40 to 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 DoneHFE 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. This test might be done if you have high iron levels in your blood. This test helps to find out if you have hemochromatosis. HFE testing locates and identifies
mutations in the HFE genes. These gene mutations are called
C282Y and H63D. How To PrepareGenerally, 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 DoneYou might have a cheek test or a blood test. For a cheek test, a health professional will gently swab or scrape the inside of your cheek to get a sample of cells. For a blood test, 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 FeelsThe 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. If you get a cheek test, you will feel gentle pressure on the inside of your cheek from the swab. You may worry or feel nervous before you have the test or
while you are waiting for the results. RisksThere is very little chance of a problem from
having a cheek test or from having a blood sample taken from a vein. If you have a blood test: - 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.
ResultsHemochromatosis 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. Hemochromatosis gene (HFE) Normal: | Mutations (C282Y or H63D) are not found in the HFE gene.
Normal results are called negative. |
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Abnormal: | Mutations (C282Y or H63D) are found in the HFE gene test.
Abnormal results are called positive. |
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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 TestThere is a very small chance that 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- The discovery of a genetic disease that is not causing symptoms now should not affect your future ability to gain employment or health insurance coverage. A law in the United States, called the Genetic Information Nondiscrimination Act of 2008 (GINA), helps protect people who have DNA differences that may affect their health. But it has some limits. For example, this law doesn't apply to life insurance, disability insurance, or long-term care insurance. And it doesn't protect people who work for
companies with fewer than 15 employees.
- 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 disease or you may have
symptoms of the disease but gene testing 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.
Other Places To Get HelpOrganizationsIron Disorders Institute (U.S.) www.irondisorders.org National Library of Medicine: Genetics Home Reference (U.S.) www.ghr.nlm.nih.gov ReferencesOther Works Consulted- Bacon, BR et al. (2011). Diagnosis and management of hemochromatosis: 2011 practice guideline by the American Association for the Study of Liver Diseases. Hepatology, 54(1): 328-343.
- National Human Genome Research Institute (2010). Learning about hereditary hemochromatosis. Available online: http://www.genome.gov/page.cfm?pageID=10001214.
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
- Powell LW (2015). Hemochromatosis. In DL Kasper et al., eds., Harrison's Principles of Internal Medicine, 19th ed., vol. 2, pp. 2514-2519. New York: McGraw-Hill Education.
- 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.
- U.S. Preventive Services Task Force (2006). Screening for hemochromatosis. Available online: http://www.ahrq.gov/clinic/uspstf06/hemochromatosis/hemochrs.htm.
CreditsByHealthwise Staff Primary Medical ReviewerKathleen Romito, MD - Family Medicine E. Gregory Thompson, MD - Internal Medicine Adam Husney, MD - Family Medicine Elizabeth T. Russo, MD - Internal Medicine Specialist Medical ReviewerMartin J. Gabica, MD - Family Medicine Current as ofJune 8, 2017 Current as of:
June 8, 2017 Last modified on: 8 September 2017
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