Months to several years before amyotrophic lateral sclerosis (ALS) symptoms arise, levels of certain blood proteins may shift dramatically. Researchers analyzed data from the long-running Pre-symptomatic Familial ALS (Pre-fALS) study to identify key proteins that may predict the emergence of clinical ALS. By anticipating the onset of symptoms, investigators could intervene with preventive therapies before the irreversible motor neuron damage characteristic of ALS sets in.