Park YH, Hodges A, Simmons A, et al. - This study was undertaken to assess if the risk of Alzheimer disease (AD) is reflected by transcriptional risk scores (TRSs), a summation of polarized expression levels of functional genes. Blood transcriptome data from Caucasian candidates, which involved AD, mild cognitive impairment, and cognitively normal controls (CN) in the Alzheimer Disease Neuroimaging Initiative (ADNI, n = 661) and AddNeuroMed (n = 674) cohorts were used. Findings suggested a significant association of blood-based TRS with AD diagnosis and neuroimaging biomarkers. In blood, CD33 and PILRA were known to be linked to the uptake of β-amyloid and herpes simplex virus 1 infection, respectively, both of which can play a role in the pathogenesis of AD.