Epigenetic Blood Markers Reveal Dementia Risk: Insights from Two Linked Studies - Video

Two new studies linked to the journal Alzheimer's & Dementia revealed that epigenetic markers in the blood could be useful for understanding dementia risk.

Researchers conducted a study on the role of DNA methylation, an epigenetic marker, in exploring how genetic and lifestyle factors impact dementia risk.

DNA methylation involves adding a chemical tag to DNA to regulate gene activity, turning genes on or off. Variations in genetic and lifestyle factors can modify these DNA methylation tags, with some factors already recognized for their potential to increase dementia risk. By evaluating DNA methylation patterns, researchers can gain insights into how these factors affect dementia risk and the underlying mechanisms that contribute to the disease.

Researchers analyzed DNA methylation at 800,000 genomic sites using blood samples from 900 individuals. Instead of spinal fluid, they chose to collect blood samples due to the lower cost and greater ease of collection.

In the first of the two papers, researchers demonstrated that DNA methylation patterns in the blood can reflect the levels of certain protein biomarkers typically measured in spinal fluid for dementia assessment. They investigated these methylation patterns alongside 15 different spinal fluid biomarkers used for diagnosing dementia, revealing alterations in the methylation status of key genes associated with several of these biomarkers.

In the second study, the team developed epigenetic risk scores based on blood DNA methylation patterns to represent 14 established dementia risk factors. These factors included modifiable lifestyle risks like physical activity and diet, as well as non-modifiable factors such as age and heart disease.

Overall, researchers demonstrated that their epigenetic risk scores can enhance the prediction of cognitive decline and the onset of dementia, even at early stages. Early detection is essential for improving lifestyle management and accessing potential new treatments. The paper underscores the role of genetic, lifestyle, and environmental factors in the development and progression of dementia, emphasizing their influence through epigenetic mechanisms.

Reference: Smith, R. G., Pishva, E., Kouhsar, M., Imm, J., Dobricic, V., Johannsen, P., Wittig, M., Franke, A., et al(2024). Blood DNA methylomic signatures associated with CSF biomarkers of Alzheimer's disease in the EMIF-AD study. Alzheimer's & Dementia. https://doi.org/10.1002/alz.14098

Koetsier, J., Cavill, R., Reijnders, R., Harvey, J., Homann, J., Kouhsar, M., Deckers, K., et al (2024). Blood-based multivariate methylation risk score for cognitive impairment and dementia. Alzheimer's & Dementia. https://doi.org/10.1002/alz.14061