This study looks at the neurofilament light chain (NfL) in the blood of people with amyotrophic lateral sclerosis (ALS), a disease affecting the nervous system. NfL can help understand how ALS progresses, how long it lasts, and how different types of ALS develop. The study includes 3,000 ALS patients and uses a special method called Single Molecule Analysis (SIMOA) to measure NfL levels. The goal is to see if NfL can be a marker for ALS progression and treatment. The study will also explore different forms of ALS based on motor neuron involvement, which are the cells that control muscle movement. People 18 and older diagnosed with ALS can participate if they agree to provide blood samples and allow the use of their medical data.

• Study involves blood samples from 3,000 ALS patients.
• Participants must be at least 18 years old and diagnosed with ALS.
• Agreement to share medical data is required.