Did you know that a simple quirk in your genes could have a big say in your brain health as you age—especially if you’re a bloke?
New Australian research has uncovered a surprising link between a common genetic variant and a doubled risk of dementia in men, shining a spotlight on the importance of understanding our genetic makeup as we get older.
Let’s break down what this means for you, your mates, and your family.
The gene in question: HFE and the H63D variant
The study, published in the prestigious journal Neurology, focused on the HFE gene, which plays a crucial role in regulating iron levels in the body.
You might have heard of this gene before in relation to haemochromatosis—a condition where the body absorbs too much iron, leading to a range of health issues.
Here’s the kicker: about one in three people carry a single copy of a particular HFE variant called H63D, and one in 36 carry two copies.
The research found that men with two copies of this variant are more than twice as likely to develop dementia compared to those without it.
For women, however, the risk doesn’t seem to increase in the same way.
Why does this matter?
Dementia is a growing concern in Australia, with over 400,000 people currently living with the condition—and about a third of them are men.
While we’ve long known that age, lifestyle, and family history play a role in dementia risk, this study adds a new piece to the puzzle: your genes.
Professor John Olynyk from Curtin Medical School, one of the study’s co-authors, explains: ‘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.’
What’s going on in the brain?
You might be wondering: if this gene is all about iron, does that mean high iron levels are to blame?
Interestingly, the researchers found no direct link between iron levels in the blood and increased dementia risk in men with the double H63D variant.
This suggests that something else is at play—possibly inflammation or cell damage in the brain.
Professor Olynyk adds, ‘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.’
Should you get tested?
The HFE gene is already routinely tested for in Australia when doctors are checking for haemochromatosis.
But this new research suggests that perhaps men, in particular, could benefit from broader testing—not just for iron overload, but to better understand their dementia risk.
‘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,’ Professor Olynyk said.
‘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.’
What about women?
One of the most intriguing findings is that women with two copies of the H63D variant don’t seem to have the same increased risk.
The researchers aren’t sure why, but it could be due to hormonal differences, lifestyle factors, or even the way men and women’s brains respond to inflammation and cell damage. More research is needed, so watch this space.
The bigger picture: Personalised prevention and treatment
Professor Paul Lacaze from Monash University, another co-author, says, ‘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 is a great example of how Australian researchers are leading the way in tackling the big health challenges of our time.
The ASPirin in Reducing Events in the Elderly (ASPREE) trial, which provided the data for this study, involved over 19,000 healthy older people in Australia and the USA, and has become a goldmine for research into healthy ageing.
Video Credit: Curtin University / YouTube
Understanding the links between genetics and health continues to evolve, offering new insights into how we might better manage risks as we age.
Have you or someone you know been tested for genetic factors related to dementia? What are your thoughts on genetic testing as a tool for assessing health risks? Do you believe personalised prevention based on genetics could change how we approach ageing? We invite you to share your experiences and opinions in the comments below.
Also read: The subtle dementia warning sign that can appear 20 years before symptoms hit
