Presenilin-1 mutations in Alzheimer's disease

Mutations in the gene encoding the protein presenilin-1 are the most common cause of familial Alzheimer's disease1 and they often produce a different disease course from sporadic Alzheimer's and another familial form associated with mutations in the gene encoding β-amyloid precursor protein2. Here we show that a peculiar form of β-amyloid that is devoid of the first ten amino acids accumulates in the brains of patients carrying presenilin-1 mutations, and is more abundant than in subjects affected by the other types of Alzheimer's.