A higher proportion (p<0.0001 for all comparisons) of patients had serum NfL values above this cut-off: 16/20 (80.0%) in AD, 13/19 (68.4%) in GBS, 42/46 (91.3%) in ALS, compared to HC (6/67, 9.0%). This evidence concerns the gene NEFL and Alzheimer disease.