Scientists have identified a genetic variant in the haemochromatosis (HFE) gene that doubles the risk of dementia in older men, according to a study led by Monash and Curtin Universities. The research, published in the journal *Neurology*, analyzed data from over 19,000 Australians and Americans, revealing that men carrying two copies of the H63D variant are at least twice — and up to four times — more likely to develop dementia. The study found that while the mutation does not affect women, it highlights a gender-specific impact that remains a mystery to researchers.
Dr. John Olynyk, a co-author of the study and a professor at Curtin Medical School, explained that the HFE gene normally regulates iron levels in the body, but the variant appears to influence brain pathways differently in men. “It is only men who have two copies of the variant that are at risk,” he noted, emphasizing that women are not affected. The study’s authors suggest that further research is needed to determine why this sex-specific risk exists, potentially leading to more personalized prevention strategies for men.
While the mutation itself cannot be changed, the researchers believe that understanding the brain mechanisms it influences could eventually lead to new treatments. Dr. Olynyk pointed out that the HFE gene is already routinely tested for in the West, primarily for haemochromatosis, a condition that causes excessive iron absorption. He recommended expanding these tests to older men to identify those at higher dementia risk. However, the study’s co-author, Professor Paul Lacaze from Monash University, emphasized that no direct link was found between iron levels and dementia, suggesting other factors may be at play, such as inflammation and cellular damage.
The study’s primary limitation was its focus on an Australian population, meaning the findings may not apply universally. Dr. Olynyk acknowledged that further research is needed to replicate the results in other countries. Additionally, the researchers acknowledged that while genetic factors cannot be altered, adopting a healthy lifestyle—such as regular exercise, a balanced diet, limiting alcohol, and staying mentally active—may help mitigate the risk. The study also highlighted the role of maintaining overall health, as various environmental and genetic factors can influence dementia risk.