Low specificity to multiple sclerosis against other neurodegenerative conditions is one limitation of, for example, serum or plasma neurofilament light chain (NfL) as a diagnostic as opposed to prognostic or treatment effect biomarker74, even as parallel developments in machine learning and networking technologies are otherwise enhancing the feasibility of automated blood-based testing in routine point-of-care use75. The gene discussed is NEFL; the disease is multiple sclerosis.