What is familial Alzheimer’s disease?
Last Reviewed: Jul 2, 2025Familial Alzheimer's disease (FAD) is a rare, genetic form of Alzheimer’s disease caused by inheriting specific mutations in one of three genes: PSEN1, PSEN2, or APP.
Like those with non-familial Alzheimer’s disease, people with FAD may experience gradual loss of memory, along with other important brain faculties, including judgment, thinking, speaking, and social skills, and sometimes difficulty with walking.
People with these mutations typically show symptoms of Alzheimer’s disease before age 65, often between 30 and 50 years old. This is why many people refer to FAD as early onset familial Alzheimer’s disease or young onset familial Alzheimer’s disease.
If a parent has a mutation in an FAD gene, there's a strong chance they could pass that mutation on to each of their children. Impacted families often see Alzheimer’s disease affect many loved ones (siblings, uncles, aunts, cousins) across multiple generations.
Familial Alzheimer’s disease goes by many different names.
It is also known as:
Dominantly inherited Alzheimer’s disease (DIAD)
Early onset familial Alzheimer’s disease (EOFAD)
Autosomal dominant Alzheimer’s disease (ADAD)
Genetic Alzheimer’s disease
You can learn more about Familial Alzheimer’s Disease in this overvew ⧉ from UCSF.