a common genetic disorder once believed to pose a low health risk actually makes men 10 times more likely to develop liver cancer, a new study has found.
haemochromatosis, also known as the “celtic curse” due to its high prevalence in men of european ancestry living in the u.k. and north america, is a condition that causes certain people to absorb too much iron from their diet. new research conducted at the university of exeter, in conjunction with the university of western ontario, found that seven per cent of men with two copies of the malfunctioning haemochromatosis gene develop cancer by the age of 75 compared to a rate of just 0.6 per cent in those without the disorder.
“unfortunately, haemochromatosis is often diagnosed too late,” said janice atkins, the study’s lead author and a research fellow at the university of exeter, in a release . “earlier diagnosis could prevent so much unnecessary disease.”
previous research by the same team found the genetic disorder makes liver cancer four times more likely while doubling the risk of arthritis and fragility in older populations. it also increases the likelihood of chronic pain and diabetes. the condition is generally accompanied by fatigue, muscle weakness and joint pain, symptoms that are often misdiagnosed as the effects of old age.
haemochromatosis poses a greater risk to men because women typically decrease the iron in their system naturally through menstruation and childbirth. “tragically, men with the haemochromatosis faulty genes have been dying of liver cancer for many years, but this was thought to be rare,” said david melzer, the team lead. “we were shocked to find that more than seven per cent of men with two faulty genes are likely to develop liver cancer by age 75, particularly considering that the u.k. has the second highest rate of these faulty genes in the world.”
haemochromatosis is also one of the most common genetic disorders in canada, affecting one in 327 canadians, according to the canadian liver foundation . in order to develop the hereditary condition, patients must be passed on two defective genes — one from each parent. because the liver is the first organ the body uses to store an overabundance of iron, damage arises here first and can lead to cirrhosis and then cancer if not detected and treated.
to arrive at their conclusions, researchers consulted the data of 2,890 men and women with two copies of the faulty gene who were enrolled in the u.k. biobank — a massive health database of british men and women compiled from 2006 to 2010. the patients, who were between 40 and 70 years of age at the start of the study, were followed for nine years by researchers. of the 1,294 men with faulty genes, 21 developed liver cancer, with 14 dying from the disease. half of these men had not been diagnosed with haemochromatosis before the cancer developed.
“physicians and scientists have long acknowledged that iron overload is an important co-factor fuelling the development of many serious diseases, including cancer,” said jeremy shearman, a liver disease specialist and advisor to haemochromatosis u.k . “this research is a vital step towards quantifying that risk and should raise awareness of the importance of iron in the minds of both clinicians and patients. measurement of iron stores and recognition of the genetic risk of iron overload needs to become a routine part of health assessment and monitoring in the uk.”
mark williams, a 54-year-old business man, discovered he possessed the faulty genes after requesting a second opinion for a sore shoulder. his father, mike, died from cancer caused by haemochromatosis five years earlier so he decided to take extra precautions. after his diagnosis — and 12 months of venesection, or regular bloodletting — his iron levels are back where they should be.
“i can’t believe how lucky i am,” he told the irish news . “my dad went his entire life with this terrible condition and he was completely unaware. he thought he’d pulled a muscle in his back, but by the time he went to hospital, he died of liver cancer a week later. it was devastating and such a shock.
“ if i hadn’t seen a doctor who spotted the signs, i could be looking at developing cancer in my 70s too.”
dave yasvinski is a writer with healthing.ca