Genomics and Health
July is National Hemochromatosis Awareness Month
Hemochromatosis is an iron storage disorder that can cause the body to absorb too much iron from foods and other sources, such as multivitamin supplements with iron. This extra iron can gradually build up in the body’s tissues and organs, particularly in the liver cells, heart, pancreas, joints, and pituitary gland. If left untreated, this iron buildup may lead to tissue and organ damage over time.
Genetics can play a major role in hemochromatosis
Primary hemochromatosis, also called hereditary hemochromatosis, is an inherited disorder. Secondary hemochromatosis is caused by anemia, alcoholism, and other disorders. In the United States, the most common form of hemochromatosis in adults is hereditary hemochromatosis.
Hereditary hemochromatosis is caused mainly by specific inherited alterations (mutations) in the HFE gene. When an individual inherits two altered copies of the gene—one from each parent—they are at risk of developing high iron levels which may lead to illness or organ damage over time. However, most people born with two altered copies of the HFE gene will not develop serious complications. People who inherit an altered gene from only one parent are carriers for the disorder, but are not typically affected themselves.
Men and women have the same chance of inheriting two copies of the altered HFE gene. However, men are more likely than women to develop complications and at an earlier age because women lose excess iron in the blood naturally during menstruation and pregnancy.
Family history is an important risk factor for hereditary hemochromatosis. People who have a close biological relative with hereditary hemochromatosis due to two altered HFE genes have a higher chance of having the altered HFE gene themselves. For example, if you have hereditary hemochromatosis due to two altered HFE genes, then your siblings have a 1 in 4 chance of also having two altered HFE genes.
Hereditary hemochromatosis is one of the most common genetic disorders in the United States. People of Northern European descent have a higher chance of having an altered HFE gene. Hereditary hemochromatosis is more common among U.S. non-Hispanic whites, and is less common among African Americans, Asian Americans, Hispanics/Latinos, and American Indians.
Early detection of hemochromatosis is important
Two blood tests can also be used to screen people who may have iron buildup due to hereditary hemochromatosis. These blood tests measure how much iron is in the body.
The U.S. Preventive Services Task Force recommends against routine genetic screening for hereditary hemochromatosis in the asymptomatic general population, but states that individuals with a family member, especially a sibling, who is known to have hereditary hemochromatosis should be counseled regarding genetic testing.
Knowing your family health history can help you and your doctor understand your risk for hemochromatosis. It is helpful to talk with your family members about their health history, write this information down, update it from time to time, and share it with your doctor. Family health history information can help your doctor determine which tests and screenings are recommended to help you know your health risk. To learn more about family health history, visit: http://www.cdc.gov/genomics/famhistory.
Steinberg KK, Cogswell ME, Chang JC, Caudill SP, McQuillan GM, Bowman BA, Grummer-Strawn LM, Sampson EJ, Khoury MJ, Gallagher ML. Prevalence of C282Y and H63D mutations in the hemochromatosis (HFE) gene in the United States. JAMA. 2001;285:2216-22.
Learn more about hereditary hemochromatosis
- Learning About Hereditary Hemochromatosis, National Human Genome Research Institute
- HFE-Associated Hereditary Hemochromatosis, GeneReviews
Learn more about hemochromatosis
- Centers for Disease Control and Prevention:
- Hemochromatosis, Iron Disorders Institute
- Hemochromatosis, National Digestive Disease Information Clearinghouse