In human brains with early AD, intraneuronal Aβ42 accumulation in hippocampal cell bodies precedes hyperphosphorylation of tau [20, 21], and in a common mouse model of AD (3xTg-AD mouse), intraneuronal Aβ accumulation in cell bodies also precedes tau hyperphosphorylation [48, 49]. Here, MAPT is linked to Alzheimer disease.