Neurofilament light chain (NfL), a sensitive marker of neuronal injury, has emerged as a potential biomarker in various neurodegenerative and neuroinflammatory conditions, such as Alzheimer’s disease (AD) (24), Parkinson’s disease (PD) (25), multiple sclerosis (MS) (26). This evidence concerns the gene NEFL and early-onset autosomal dominant Alzheimer disease.