BACE1 and Alzheimer disease: When we combined ND using the connectivity network and baseline pathology into a multivariate linear model using regional expression patterns of several specific genes as the other tau pathology predictors, a major AD risk factor gene [12] known to increase CSF tau, Bace1 [36], a gene known to promote tau hyperphosphorylation in cultured cells [39], Hs3st2, and the gene specifically necessary for norepinephrine synthesis, Dbh [35].