MAPT and Alzheimer disease: Overall, the accumulated iron produces reactive oxygen species that can damage DNA (Melis et al., 2013), alter DNA expression by epigenetic mechanisms (Kwok, 2010), induce post translational modifications to proteins (Perluigi et al., 2012), and drive tau pathology (Mondragón-Rodríguez et al., 2014), suggesting iron’s importance as a potential early driver in AD.