Multiple systematic meta-analyses indicate elevated peripheral whole blood concentrations of inflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), IL-1β, transforming growth factor beta (TGF-β), IL-12, and IL-18 in AD patients relative to age-matched healthy controls (Swardfager et al., 2010; King et al., 2018; Walker et al., 2019a). This evidence concerns the gene IL6 and Alzheimer disease.