Haemochromatosis, also known as 'iron overload', is Ireland's most common genetic condition, however as many as 20,000 people may be unaware that they have it, the Irish Haemochromatosis Association has said.

This week is World Haemochromatosis Awareness Week (June 1-7) and the association is using this event to raise awareness of the condition and its symptoms.

Haemochromatosis is a hereditary condition in which excessive amounts of iron are absorbed from the diet. This iron is deposited in various organs, including the liver, pancreas and heart, as well as the joints.

Since iron builds up slowly, symptoms may not appear until a person is in their 30s or 40s. Symptoms can include unexplained fatigue, arthritis particularly in the first and second knuckles and/or ankles, diabetes, liver disorders, discolouration and/or bronzing of the skin, mood swings and diminished sex drive.

Most people with haemochromatosis will develop at least one or two of the above symptoms, although possibly in a mild form. When undetected and untreated, iron overload can result in severe organ damage and premature death.

Treatment is venesection, which means the removal of blood. It is just like giving a blood donation. How often you will need to undergo venesection will depend on how far advanced your condition is.

Treatment is most effective when begun early as it can successfully prevent organ damage. If damage has already occurred, treatment should halt any further damage and in most cases, bring about some improvement.

Haemochromatosis is more common in Ireland than anywhere else in the world, as one in five people carry the gene and one in every 83 Irish people carry two copies of the gene and are therefore predisposed to develop iron overload.

"Though life threatening, once diagnosed in time before organ damage has occurred, haemochromatosis can be successfully treated and patients go on to fully live their lives, without any impact.

"Ireland has more cases than anywhere else in the world and we want everyone to understand what haemochromatosis is and how important early diagnosis is. We believe that there are 20,000 undiagnosed cases currently in Ireland," explained the association's chairperson, Margaret Mullett.

Ms Mullett sadly lost her husband, Dr George Mullet, to the condition. He was diagnosed with haemochromatosis only six weeks before he died in June 2000, while awaiting a heart transplant in the Mater Hospital. All five of their adult children were then tested and were diagnosed with the condition and by a strange coincidence, Ms Mullett also tested positive for it.

She and her five children have all received treatment and are now living their lives unaffected by the condition.

According to Prof Suzanne Norris, a consultant in hepatology and gastroenterology in St James's Hospital in Dublin, ill health and complications from haemochromatosis can be prevented by simple treatment.

"Life expectancy in treated non-cirrhotic patients is normal. Early diagnosis is therefore critical," she emphasised.

While most of the condition's symptoms can be found in other conditions, arthritis in the first two fingers joints is "highly suggestive" of haemochromatosis, the association noted.

Haemochromatosis can be diagnosed by a blood-based genetic test combined with a test to identify high levels of iron in the blood. This can be organised by your GP.

"We hope that more people will listen to their bodies, talk to their GPs and undergo the simple tests to diagnose the condition. This is an especially difficult time for so many people with the COVID-19 global pandemic, but we would like to encourage people to contact their GPs if they experience symptoms," Ms Mullett said.

For more information on the condition and the Irish Haemochromatosis Association, click here.