Early-onset Alzheimer's disease
（重定向自Familial Alzheimer disease）
![Familial Alzheimer disease is inherited in an autosomal dominant fashion.](/Images/godic/202501/12/Autosomal_Dominant_Pedigree_Chart.svg5123.png")
![Processing of the amyloid precursor protein](/Images/godic/202501/12/APP_processing5123.png")
Early-onset Alzheimer's disease, also called early-onset Alzheimer's, or early-onset AD, is the term used for cases of Alzheimer's disease diagnosed before the age of 65. It is an uncommon form of Alzheimer's, accounting for only 5-10% of all Alzheimer's cases. Approximately 13% of the cases of early-onset Alzheimer's are familial Alzheimer's disease, where a genetic predisposition leads to the disease. The other incidences of early onset Alzheimer's, however, share the same traits as the 'late onset' form of Alzheimer's disease, and little is understood about how it starts.