Can Blood Tests Predict ALS Before It Strikes? Here's What Scientists Found

Key Points:

• Researchers have identified a panel of 19 proteins in blood plasma that can predict which carriers of ALS-linked genes will develop the disease and estimate the timing of symptom onset years in advance, improving on the current best marker, NEFL.
• The study analyzed 516 blood samples from 137 participants over 18 years in the Pre-Symptomatic Familial ALS study, using machine learning to track protein changes before symptoms appeared and achieve prediction accuracy scores up to 0.889 within one year of onset.
• Many proteins in the panel relate to muscle biology, suggesting muscle-related changes may begin years before ALS symptoms, challenging the conventional focus solely on nerve cell degeneration.
• The panel estimated the time to phenoconversion with an average error of 1.6 years, which could help design prevention trials by identifying candidates likely to develop symptoms within a specific timeframe.
• While promising, the panel requires further validation across diverse genetic backgrounds and simpler clinical testing methods before it can be used routinely, but it marks a significant advance toward early ALS detection and intervention.