Shedding light on the potential for causation, Dominy et al. further conducted a series of preclinical studies, demonstrating not only that oral infection of BALB/c mice with Pg could lead to brain colonisation, neurodegeneration, and induction of the stereotypical AD marker Aβ1–42 but also that gingipains had neurodegenerative effects both in vivo and in vitro, exerting harmful impact on tau. Here, MAPT is linked to Alzheimer disease.