GAP43 and Alzheimer disease: We found there were strong correlations between CSF GAP-43 and T-tau in CN ε4−, CN ε4+, MCI ε4−, MCI ε4+, AD ε4−, and AD ε4+ groups (rs = 0.711, p < 0.001; rs = 0.709, p < 0.001; rs = 0.751, p < 0.001; rs = 0.742, p < 0.001; rs = 0.453, p = 0.003; rs = 0.696, p < 0.001; respectively) (Table 2 and Figure 2B).