MAPT and Alzheimer disease: As shown in Table 2, Figures 1, 2, and Supplementary Figures 1, 2, there were significantly higher levels of Aβ1–40, P-tau, and P-tau/T-tau ratio, and lower levels of Aβ1–42 and Aβ1–42/Aβ1–40 ratio in the AD and AC groups, compared with the NC group.