PSEN2 and Alzheimer disease: In fact, many proteins that cause hereditary AD, including amyloid-β precursor protein (Szpankowski et al., 2012), presenilin 1, presenilin 2 (Gunawardena et al., 2013) and β-secretase (Lee et al., 2005) can induce axonal transport defects and lead to the development of axonopathy.