Higher levels of SV2A (Fig. 4c, P = 0.0071) were detected in AD at Braak stages 0–II than in V–VI, similar as the higher levels of SYP in AD at Braak stages 0–II than at stages V–VI (Fig. 4i, P = 0.0059) and III–IV (Fig. 4i, P = 0.0148). This evidence concerns the gene SYP and Alzheimer disease.