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What’s Inside Responding to the reader Toxin Research Research Views Cellular construction Staying alive Stroke: brain attack Research outside the lab The road to commercialization 2005-2006 Lionel McLeod Scholarship winner AHFMR announces $48 million for health research Reader Resources Responding to the reader AHFMR frequently receives letters requesting information about Heritage research or about various medical conditions. “Responding to the Reader” is an AHFMR Research News feature intended to provide up-to-date information related to readers’ questions, with the help of experts in the Alberta research community. AHFMR cannot provide medical advice, however; please see your family physician about your specific health concerns. Hemochromatosis is a condition in which the body absorbs too much iron from the diet, resulting in a buildup of iron in organs and tissues. If untreated, the disorder can result in such significant complications as cirrhosis, diabetes, and congestive heart failure. One in 227 Canadians of northern European descent has a genetic predisposition to hemochromatosis, making it the most common genetic disorder in North America. A reader has asked whether too much iron in the body may cause cancer, a possibility which would certainly be of concern, not only to those with hemochromatosis, but also—because so many foods today are iron-fortified—to the general public. Toxin Dr. Dawna Gilchrist is a clinician-teacher at the University of Alberta who specializes in genetic disorders of adult onset, including hereditary cancers. She says there is no evidence that iron causes cells to become cancerous. “Iron is a cellular toxin,” she explains. “It can cause cell death. If you’ve got death of heart cells, you’ve got heart failure; if you’ve got death of pancreatic cells, you’ve got diabetes; and death of liver cells can cause cirrhosis. Iron kills cells; it doesn’t transform them into cancer.” Dr. Gilchrist adds that the only instance where iron could be linked to cancer is in hepatocellular carcinoma, a type of liver-cell cancer, but this rare cancer may occur in anyone with cirrhosis, not just someone with advanced hemochromatosis. The cancer is related to cirrhosis, not specifically to iron. Hemochromatosis is a relatively common disease with a variety of potential symptoms. “People who have a genetic predisposition sometimes assume that all of their health problems are related to that genetic issue; however, this isn’t necessarily the case,” says Dr. Gilchrist. For example, a patient might have both hemochromatosis and lung cancer—but the lung cancer would be associated with smoke exposure, not with iron toxicity. They are simply independent disorders. Research Patients may also assume that, because they have a genetic predisposition to store too much iron, they will develop health problems. However, a predisposition is just that. In order for damage to occur to the body, other factors (such as too much iron in the diet, overuse of alcohol, or viral hepatitis) must come into play. In a recent study by the University of Western Ontario’s Dr. Paul Adams, more than 100,000 people were screened for iron overload. Of those whom he found to have the typical genetic pattern for hemochromatosis—at the typical rate of 1 in 227 Caucasians—many had no apparent illness at all. “There are people who have this genetic pattern their whole lives and never get adverse effects,” explains Dr. Adams. “There is a huge spectrum of clinical presentation. We’re now trying to correlate some of the symptoms that might be related to iron overload with the various genetic patterns to learn more about this.” Dr. Dawna Gilchrist is an associate professor in the Division of General Internal Medicine within the Department of Medical Genetics at the University of Alberta. She is in the process of developing clinical-practice guidelines for the diagnosis and management of genetic hemochromatosis. Dr. Paul Adams is a professor in the Department of Medicine’s Division of Gastroenterology at the University of Western Ontario. He received funding from the National Institutes of Health (NIH) in the United States for the Hemochromatosis and Iron Overload Screening Study (HEIRS). Selected publication Adams PC, Reboussin DM, Barton JC, McLaren CE, Eckfeldt JH, McLaren GD, Dawkins FW, Acton RT, Harris EL, Gordeuk VR, Leiendecker-Foster C, Speechley M, Snively BM, Holup JL, Thomson E, Sholinsky P. Hemochromatosis and iron-overload screening in a racially diverse population. New England Journal of Medicine 2005 Apr 28;352(17):1769-1778. Back to Top