NRGN and Alzheimer disease: Compared to CN ε4−, CSF Ng, T-tau, and P-tau had high diagnostic accuracy for MCI ε4+ (Table 2 and Figure 3B), AD ε4− (Table 2 and Figure 3C), and AD ε4+ (Table 2 and Figure 3D) but not MCI ε4− (Table 2 and Figure 3A).