Hemochromatosis is a condition where the body absorbs and stores too much iron, leading to an overload that can damage organs. This inherited genetic disorder can cause serious health issues. A hemochromatosis genetic test helps diagnose the condition or assess an individual’s risk.
Understanding Hemochromatosis
Hemochromatosis occurs when the body accumulates excessive amounts of iron. Normally, the body controls iron absorption from food, but in hemochromatosis, this regulation is disrupted. This leads to iron buildup in organs like the liver, heart, and pancreas, which can progressively harm tissues and potentially cause organ failure.
Symptoms of hemochromatosis include fatigue, weakness, and joint pain, especially in the knees and hands. Other symptoms include abdominal pain, a loss of interest in sex, or a darkening of the skin, sometimes described as a gray, metallic, or bronze appearance. Symptoms often emerge after age 40, with women developing them about a decade later than men, partly due to iron loss through menstruation.
The Genetic Test Explained
The hemochromatosis genetic test involves a blood or saliva sample. This test looks for mutations in the HFE gene, which regulates iron absorption. The two most common mutations associated with hereditary hemochromatosis are C282Y and H63D.
The C282Y mutation involves a change at position 282 of the HFE protein, where a cysteine residue is replaced by a tyrosine. This alteration affects the HFE protein’s interaction with the transferrin receptor, which is involved in cellular iron uptake. The H63D mutation involves a different change at position 63, substituting a histidine residue with an aspartic acid, also disrupting iron regulation. These mutations lead to impaired iron sensing, causing the body to absorb more iron than needed and store it in tissues.
Interpreting Your Results
Interpreting hemochromatosis genetic test results requires understanding the specific gene mutations identified. If the test shows you are homozygous for the C282Y mutation (C282Y/C282Y), meaning you have two copies, you are at a high risk of developing iron overload. This genotype accounts for a majority of hereditary hemochromatosis cases.
If you are compound heterozygous (e.g., C282Y/H63D), having one copy of each mutation, your risk of developing iron overload is increased, though often less severe than C282Y homozygosity. Individuals heterozygous for C282Y (one mutated copy and one normal gene) generally do not have an increased risk of iron overload themselves, but are considered carriers and could pass the gene to their children. It is important to remember that a positive genetic test indicates a predisposition to hemochromatosis, but does not mean you have active iron overload or will develop symptoms. Confirmation of active iron overload requires further blood tests, such as serum ferritin and transferrin saturation, which measure stored and circulating iron levels. A negative result means no common HFE gene mutations were found.
Life After a Diagnosis
Following a confirmed diagnosis of hemochromatosis, regular monitoring of iron levels becomes standard care. This involves periodic blood tests to track serum ferritin and transferrin saturation. The primary treatment for reducing iron levels is therapeutic phlebotomy, a procedure that removes a pint of blood at regular intervals, similar to a blood donation.
Initially, phlebotomy may be performed weekly or monthly until iron levels return to a healthy range, a process that can take weeks to years depending on the initial iron burden. Once iron levels are normalized, the frequency is reduced, often to every one to three months or a few times a year for ongoing maintenance. Lifestyle considerations include avoiding iron supplements, limiting excessive alcohol intake, and restricting high-iron foods or vitamin C supplements, which can enhance iron absorption. Due to the hereditary nature of hemochromatosis, screening of immediate family members is often recommended to identify others at risk.