Alzheimer's disease (AD) is an age-related progressive neurodegenerative disorder characterized by the presence of amyloid plaques consisting of aggregated amyloid beta (Aβ) peptides together with neurofibrillary tangles (NFTs), neuropil threads and dystrophic neurites composed of abnormally phosphorylated tau protein. This evidence concerns the gene MAPT and early-onset autosomal dominant Alzheimer disease.