MTAG revealed 358 genome-wide significant multi-trait associations (p < 5 × 10−8; pairwise r2 < 0.6; Figure 1): 149 for AD (top hit at rs1081105, within the APOE gene, p = 2.36 × 10−180), 70 for PD (top hit at rs356219, within the SNCA gene, p = 6.01 × 10−41) and 139 for MDD (top hit at rs2232429, within the ZSCAN12 gene, p = 6.41 × 10−19). Here, APOE is linked to major depressive disorder.