Once pathogens and inflammatory markers migrate to the brain and penetrate the blood–brain barrier, they can influence microglial activation, Aβ deposition, tau protein phosphorylation, and vascular changes that could all contribute to the pathology of AD (Aarabi, Thomalla, Heydecke, & Seedorf, 2018; Lewy et al., 2018; Uppoor, Lohi, & Nayak, 2013). The gene discussed is MAPT; the disease is Alzheimer disease.