HONG KONG, Jan 17 (Reuters) - A study in Australia has shown that an inherited disorder, which causes iron overload, is more common than previously thought and that more men go on to develop the potentially fatal disease and other complications.

Hereditary hemochromatosis causes the body to absorb up to three times the normal amount of iron. Over the years, the excess iron builds up in vital organs, joints and tissues, where it can cause debilitating and potentially fatal conditions, including liver and heart disease, diabetes and arthritis.

The disorder is linked to a certain defective gene called C282Y, and people who inherit two copies of this gene, one from each parent, would be susceptible to the disease.

Previous studies have shown that one in 200 people with northern European ancestry have this genetic marker, but it was never clear what percentage of people with these defective genes go on to develop the disease. Some estimates have put the percentage at less than 1 percent.

But a 12-year study in Australia found that the far more men, or 28.4 percent, eventually developed the disease, compared to only 1.2 percent of women with the defective genes.

"In persons who are homozygous for the C282Y mutation, iron overload-related disease developed in a substantial proportion of men but in a small proportion of women," the researchers wrote in an article published in the New England Journal of Medicine.

The scientists tracked 31,192 participants over 12 years, 203 of whom were C282Y homozygous, or people who possessed both copies of the defective gene.

The subjects were checked for their levels of serum ferritin, a protein which binds to iron and stores it in the body.

Those with higher levels of the protein were later found to be at higher risk of developing symptoms and complications of the disease.

"This study gives us important new understanding into hemochromatosis, particularly how complications from the disease are common among men with the genetic predisposition for it," wrote Bruce Bacon, professor of internal medicine and director of the division of gastroenterology and hepatology at the St Louis School of Medicine, in an editorial accompanying the article. (Reporting by Tan Ee Lyn; Editing by Jeremy Laurence)

AlertNet news is provided by