In Alzheimer disease (AD), for example, there are extracellular depositions of amyloid-β (Aβ) plaques and intracellular accumulations of neurofibrillary tangles of tau (Glenner and Wong, 1984; Grundke-Iqbal et al., 1986). This evidence concerns the gene MAPT and early-onset autosomal dominant Alzheimer disease.