Summary: New research reveals that men who carry two copies of a common genetic variant in the HFE gene are more like the probability of developing dementia, while women with the same variant are not affected. The variant, known as H63D, is linked to hemochromatosis and is present in approximately 1 in 36 people.
Interestingly, the researchers did not find a direct connection between high levels of iron and the risk of dementia, inspecting other biological mechanisms such as inflammation or neuronal damage. These findings could guide more personalized dementia prevention strategies, particularly for men who carry this gene.
Key facts:
Specific sex risk: men with two copies of the H63D gene variant have twice as a risk of dementia; Women do not. Iron levels: the highest risk seems not related to iron in the blood, which suggests that other roads are involved. Clinical potential: HFE routine tests could help identify high -risk men for previous intervention.
Source: Curtin University
New research has found that men who carry a common genetic variant have twice as probabilities to develop dementia in their lives compared to women.
The research, published in Neurology, used aspirin data in reducing events in the elderly trial (ASPREE) to investigate whether people who had variants in the hemochromatosis (HFE) gene, which is critical to regulate iron levels in the body, could have a higher risk of dementia.
The co -author, Professor John Olynyk, of the Faculty of Medicine Curtin, said that one in three people has a copy of the variant, known as H63D, while one in 36 carries two copies.
“Having only a copy of this genetic variant does not affect someone’s health or increases their risk of dementia. However, having two copies of the variant that doubled the risk of dementia in men, but not in women,” said Professor Olynyk.
“While the genetic variant itself cannot be changed, the paths of the brain that affect, that lead to the damage that causes dementia, it could be treated if we understand more about it.”
Professor Olynyk said that more research was needed to investigate why this genetic variant increased the risk of dementia for men, but not women.
“The HFE gene is routinely proven in most Western countries, including Australia, when evaluating people for hemochromatosis, a disorder that makes the body absorb too much iron. Our findings suggest that perhaps this test could be offered more broadly,” said Professor Olynyk.
“While the HFE gene is essential to control iron levels in the body, we do not find a direct link between blood iron levels and increase the risk of dementia in affected men.
“This points to other mechanisms at stake, possibly implying the greatest risk of brain injury due to inflammation and cell damage in the body.”
Professor Paul Lacaze co -author of the University of Monash, said the findings could help improve the results for people at risk of developing dementia.
“More than 400,000 Australians currently live with dementia, and about a third of them are men. Understand why men with the double H63D variant have a higher risk, could pave the way for more personalized approaches to prevention and treatment,” said Professor Lacaze.
“This study is a great example of how the various research groups and Australian universities can effectively collaborate to learn more about these progressive diseases and, ultimately, improve health results for people around the world.”
The ASPREE essay was a double blind, randomized, controlled with low -daily aspirin placebo in 19,114 healthy people in Australia and the United States. Mainly carried out to evaluate the risks versus the benefits of low dose daily aspirin in this cohort, he created a healthy aging data treasure that has supported a large amount of research studies.
The research was a collaboration between the University of Curtin, the University of Monash, the University of Melbourne, the Royal Children’s Hospital, the Murdoch Children’s Research Institute and the Fiona Stanley Hospital.
On this news of genetic research and dementia
Author: Yasmine Phillips
Source: Curtin University
Contact: Yasmine Phillips – Curtin University
Image: The image is accredited to Neuroscience News
Original research: closed access.
“Genotypes of hemochromatosis and dementia of incidents in a prospective study of older adults” by John Olynyk et al. Neurology
Abstract
Genotypes of hemochromatosis and dementia incidents in a prospective study of older adults
Background and objectives
The variants in the Homeostatic Iron Regulator (HFE) Gen prevail among the individuals of European descent and have been related to a higher risk of dementia. This study aimed to evaluate the effects of HFE Variants P.CYS282TYR and P.HIS63ASP in serum ferritin levels and the incidence of dementia in a cohort of initially healthy older adults.
Method
This prospective longitudinal study used aspirin data to reduce events in the elderly. The participants had no history of cardiovascular disease, dementia or cognitive impairment in registration. The genotyped for the VFE variants P.CYS282TYR and P.HIS63SP was performed using microarrays, and the basal concentrations of serum ferritin were measured in peripheral blood samples.
Dementia diagnoses were confirmed by a adjudication committee during a medium tracking of 6.4 years. The associations were evaluated using proportional risks of adjusted COX for related covariables.
Results
The study included 12,174 healthy and unrelated participants of European descent of 70 years or more, comprising 5,583 men (45.9%) and 6,591 women (54.1%). The median age was 73.7 years (interquartile range (IQR): 71.6–76.9) for men and 73.9 years (IQR: 71.7–77.5) for women.
Compared to the wild type group, men with P.CYS282TYR+/+ (P = 0.048) and P.CYS282TYR+/P.HIS63ASP+ GENOTYPOS (P <0.001) had significantly higher basal ferritin levels. Women with p.his63asp+/+ (p = 0.015) and p.cys282tyr+/p.his63asp+ (p <0.001) Genotypes also exhibited high levels of ferritin. There was no significant association between the basal levels of serum ferritin and the risk of dementia.
However, men with P.His63asp+/+ genotype had a significantly higher risk of incident (adjusted danger ratio = 2.39, 95% IC 1.25–4.57, p = 0.009) compared to those without HFE variations. This association was not observed in women.
Discussion
Among the initially healthy older adults, the homozygosity of HFE P.HIS63ASP was associated with a higher risk of dementia incidents in men but not in women. These findings highlight a possible specific genetic risk factor for dementia and guarantee greater research on the underlying mechanisms that link p.his63asp and dementia.
