Specifically, results of the TWAS analyses suggest that GRIN2D SNPs lower synaptic functioning (i.e., lead to higher non-AD synaptic functioning PC5 scores) by decreasing expression of ZSWIM9 (Z =  − 5.57, p = 1.3 × 10−8) and GRIN2D (Z =  − 5.03, p = 1.5 × 10−7), as well as by increasing the expression of SLC17A7 (Z =  + 4.74, p = 1.1 × 10−6). This evidence concerns the gene GRIN2D and Alzheimer disease.