3. Biomarker characteristics:a. Studies assessing biomarkers that are measurable in blood, cerebrospinal fluid (CSF), saliva, muscle biopsies, or other biological samples.b. Focus on neurofilament light chain (NFL), retroviral markers, inflammatory markers, genetic markers, or imaging biomarkers related to ALS/MND.c. Biomarkers utilized in clinical trials for patient stratification, disease monitoring, treatment efficacy, or surrogate endpoints. The gene discussed is NEFL; the disease is amyotrophic lateral sclerosis.