Breakthrough finger-prick blood test shows promise for early Alzheimer's detection - Video

Diagnosing Alzheimer's disease may soon be as simple as pricking a finger. In a landmark study published in Nature Medicine, scientists have shown that tiny finger-prick blood samples collected at home and mailed to laboratories can accurately detect key biomarkers of Alzheimer’s disease.

Alzheimer’s is typically confirmed through expensive brain scans or invasive spinal fluid tests. Recent discoveries, however, have identified specific blood biomarkers such as phosphorylated tau (p-tau217), which strongly indicate Alzheimer’s pathology. The challenge has been making blood testing widely accessible, especially in communities lacking medical infrastructure or specialized staff for blood draws.

The DROP-AD project took on that challenge, enrolling 337 participants across seven European medical centers. Researchers used a method that required just a few drops of blood collected from a fingertip and dried on a card, known as a dried blood spot (DBS) sample. These cards could be sent to laboratories without refrigeration, maintaining stability for analysis. Using advanced lab assays, the team measured three major biomarkers linked to Alzheimer’s and other neurological changes: p-tau217, glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL).

Results were striking. The finger-prick samples mirrored standard blood test results with 86% accuracy in detecting Alzheimer’s-related changes found in spinal fluid—an impressive match for such a simple collection method. The University of Exeter played a crucial role by testing self-collected samples from UK participants, who successfully followed remote instructions without professional assistance.

Beyond Alzheimer’s, the approach shows promise for studying conditions like Parkinson’s disease, ALS, and multiple sclerosis, all of which involve neurodegeneration. Researchers believe this innovation could make global research and early detection far more inclusive by reaching populations that were previously underrepresented in clinical studies.

While not yet ready for routine diagnosis, the method marks a pivotal step toward at-home brain health testing—bringing the promise of early Alzheimer’s detection quite literally to people’s fingertips.

REFERENCE: Huber, H., Montoliu-Gaya, L., Brum, W.S. et al. A minimally invasive dried blood spot biomarker test for the detection of Alzheimer’s disease pathology. Nat Med (2026). https://doi.org/10.1038/s41591-025-04080-0