Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disorder of the central nervous system and presents the most common form of age-associated dementia. Mutations in amyloid precursor protein (APP), presenilin-1 (PSEN1) or presenilin-2 (PSEN2) genes cause familial AD (FAD) in an autosomal dominant manner [1]. Specially, mutations in PSEN1 are identified to be the most common cause of FAD with complete penetrance and tend to manifest the early onset of the disease [2, 3]. Similar brain neuropathology is observed in both sporadic and familial forms of the disease, suggesting that common cellular mechanisms may be responsible for the development of AD [4]. Therefore, studies in FAD patients with known genetic defects have greatly contributed to our understanding of AD at molecular level.
