These included numerous BBB regulation-associated genes (e.g. Iqgap1, Ptprb, Timp3, and Flt1) and AD-associated genes (including the P-glycoprotein gene Abcb1a, Adamts1, Ahnak, and Mecom; Supplementary Fig. 6a–d). This evidence concerns the gene ABCB1 and Alzheimer disease.