Common Genetic Variation Doubles Dementia Risk in Men, Study Finds

New research suggests that men with a common genetic variation may be twice as likely as women to develop dementia over their lifetime.

Having just one copy of this gene variant does not impact someone’s health or increase their risk of dementia. However, having two copies of the variant more than doubled the risk of dementia in men, but not women. While the genetic variant itself cannot be changed, the brain pathways which it affects, leading to the damage that causes dementia, could potentially be treated if we understood more about it.

John Olynyk, Professor, Curtin University

Professor Olynyk noted that further research is needed to understand why this genetic mutation increases dementia risk in men but not in women.

“The HFE gene is routinely tested for in most Western countries, including Australia, when assessing people for haemochromatosis, a disorder that causes the body to absorb too much iron. Our findings suggest that perhaps this testing could be offered to men more broadly. While the HFE gene is critical for controlling iron levels in the body, we found no direct link between iron levels in the blood and increased dementia risk in affected men. This points to other mechanisms at play, possibly involving the increased risk of brain injury from inflammation and cell damage in the body.” Professor Olynyk explained.

Co-author Professor Paul Lacaze of Monash University added that the findings could help improve outcomes for people at higher risk of developing dementia.

More than 400,000 Australians are currently living with dementia, with around a third of those being men. Understanding why men with the double H63D variant are at higher risk could pave the way for more personalised approaches to prevention and treatment. This study is a great example of how diverse Australian research groups and universities can collaborate effectively to learn more about these progressive diseases and ultimately improve health outcomes for people around the world.

Paul Lacaze, Study Co-Author and Professor, Monash University

The ASPREE trial was a double-blind, randomized, placebo-controlled study involving 19,114 healthy older adults in Australia and the United States. While its main aim was to evaluate the risks and benefits of daily low-dose aspirin, the trial also produced extensive data on healthy aging, which has supported numerous follow-up studies.

Video Credit: Curtin University