We've updated our Privacy Policy to make it clearer how we use your personal data. We use cookies to provide you with a better experience. You can read our Cookie Policy here.

Advertisement

Understanding Dementia Risk Through Blood Epigenetic Markers

DNA double helix
Credit: Geralt/ Pixabay.
Listen with
Speechify
0:00
Register for free to listen to this article
Thank you. Listen to this article using the player above.

Want to listen to this article for FREE?

Complete the form below to unlock access to ALL audio articles.

Read time: 3 minutes

New research suggests that epigenetic markers in the blood could be useful for understanding dementia risk.


Two linked papers from the University of Exeter and Maastricht University have together progressed research to show the potential for DNA methylation, an epigenetic marker, in understanding how genetics and lifestyle factors influence dementia risk.


DNA methylation is a chemical tag added to DNA, which can turn genes on and off. Genetic and lifestyle factors can alter the levels of the DNA methylation tag on genes, with some of these factors already known to increase the risk of developing dementia. By assessing DNA methylation this can help scientists understand the extent to which these different factors influence risk of dementia and the mechanisms by which they bring about disease.

Want more breaking news?

Subscribe to Technology Networks’ daily newsletter, delivering breaking science news straight to your inbox every day.

Subscribe for FREE

In the largest study of its kind, published in Alzheimer’s and Dementia: the Journal of the Alzheimer’s Association, researchers assessed DNA methylation at 800,000 sites in the genome in blood samples collected from 900 people in the European Medical Information Framework for Alzheimer’s disease Multimodal Biomarker Discovery (EMIF-AD MBD) study. The study includes extensive clinical information on participants, who all provided spinal fluid samples, which have been used for diagnosis and monitoring of Alzheimer’s disease, because it is in direct contact with the brain. However, collecting the fluid is an invasive procedure, so the team investigated whether they could instead use blood samples, through analyzing blood epigenetic signatures that are associated with Alzheimer’s disease biomarkers, as this would be cheaper and easier to collect in practice.


In the first of the two papers, led by Professor Katie Lunnon at the University of Exeter Medical School, the team showed that DNA methylation signatures in blood can mirror some protein biomarker levels in spinal fluid samples, which are used for assessing dementia. The team explored these signatures in conjunction with 15 different spinal fluid biomarkers that are used for diagnosing dementia and showed changes in the methylation status of key genes for a number of these biomarkers.


In a second linked paper in the same journal, led by Dr Ehsan Pishva at Maastricht University in the Netherlands, the team generated epigenetic risk scores using blood DNA methylation signatures as a proxy for 14 known dementia risk factors. Some of these were modifiable lifestyle risks including physical activity, diet and some were non-modifiable, such as age and having heart disease.


They showed that their epigenetic risk scores can improve the prediction of the risk of cognitive decline and dementia onset, even at early stages. Early detection is crucial to better lifestyle management, and to accessing potential new treatments.  The paper highlights how genetic, lifestyle, and environmental factors are contributing to the development and progression of dementia through epigenetic mechanisms.


Professor Katie Lunnon, at the University of Exeter Medical School, is lead author on one of the studies, and leads the Dementia Genomics Team who have previously published a number of pioneering papers exploring epigenetics in the brain and blood in different dementias. She said: “We know that a number of genetic and lifestyle factors can increase the risk of developing Alzheimer’s disease and other dementias. Epigenetics is a particularly exciting research field because it can mediate the interaction between our genetic makeup, which is fixed at conception, and environmental risks, which we can potentially modify.


Dr Ehsan Pishva, at Maastricht University, who led the other paper and leads the Dementia Systems Biology team, said: “Our epigenetic risk score can improve the prediction of risk of cognitive impairment in different populations, marking a significant advancement in dementia research. The study, which involved advanced analysis of large epigenetic datasets from multiple independent dementia cohorts, found that the epigenetic risk score was a predictor of future cognitive decline in Alzheimer’s disease and Parkinson’s disease cohorts.


“Our findings highlight the potential of using blood-derived epigenetic measurements as a non-invasive approach to assess dementia risk, paving the way for future studies to explore more personalised and preventive healthcare strategies in tackling cognitive impairment.”


Dr Richard Oakley, Associate Director of Research and Innovation at Alzheimer’s Society, said: “This study, part-funded by Alzheimer’s Society, adds to growing evidence that blood biomarkers could be used for diagnosing Alzheimer’s disease more quickly and easily in the future.  


“Current diagnostic tests such as brain scans and lumbar punctures are time-consuming, uncomfortable and not available around the UK, and currently only 2% of people with dementia can access the specialized tests needed for an accurate diagnosis. On average people also wait a year before seeing a clinician, leading to unnecessary delays, worry and uncertainty.  


“This research looked at dementia biomarkers – medical signs in the body which show whether a person has Alzheimer’s disease. The study included an investigation of the connections between biomarkers of Alzheimer’s disease which are present in spinal fluid, and possible markers in blood. Although we need further studies to confirm these findings, this work provides further evidence that blood tests are the future of diagnosis in Alzheimer’s disease, instead of individuals needing an invasive test to identify biomarkers in the spinal fluid."


References:

  1. Smith RG, Pishva E, Kouhsar M, et al. Blood DNA methylomic signatures associated with CSF biomarkers of Alzheimer’s disease in the EMIF-AD study. Alzheimer’s Dement. 2024. doi: 10.1002/alz.14098
  2. Koetsier J, Cavill R, Reijnders R, et al. Blood-based multivariate methylation risk score for cognitive impairment and dementia. Alzheimer’s Dement. 2024. doi: 10.1002/alz.14061

This article has been republished from the following materials. Note: material may have been edited for length and content. For further information, please contact the cited source. Our press release publishing policy can be accessed here.