The AD group also showed significantly higher concentrations than controls for tau N-mid-region (AD, 294.7 (179.2) pg/mL; controls, 153.4 (63.8) pg/mL), tau N-224 (10.8 (8.2) pg/mL; 6.0 (3.4) pg/mL) and non-phosphorylated tau (77.2 (53.4) pg/mL; 39.4 (17.6) pg/mL). Here, MAPT is linked to Alzheimer disease.