Second, TWAS analyses combining large eQTL (i.e., brain from ROS/MAP) and GWAS summary statistics on AD risk and related brain phenotypes, support our conclusion of a relevant association signal in the GRIN2D region and suggest that the molecular effects may be mediated by affecting the expression on GRIN2D (see section “ Functional characterization and related phenotypes”, Additional file 1: Table S10). This evidence concerns the gene GRIN2D and Alzheimer disease.