NfL is a cytoskeletal protein, expressed mainly in large fibre myelinated axons20 which is thought to be passively released into CSF in response to neurological insults including head trauma,21 neuroinflammatory relapses in multiple sclerosis,6 and a range of neurodegenerative diseases, reflecting disease intensity.22 The gene discussed is DNM2; the disease is neurodegenerative disease.