Your browser does not support javascript:   Search for gard hereSearch for news-and-events here.

Diseases

Genetic and Rare Diseases Information Center (GARD)

Print friendly version

Alzheimer disease familial


Other Names for this Disease

  • FAD
  • Familial Alzheimer disease
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.

Inheritance

Newline Maker

What is early-onset Alzheimer disease and how is it inherited?

Early-onset Alzheimer disease is a form of Alzheimer disease that begins to affect people before the age of 65. Fewer than 2% of families with Alzheimer disease have early-onset familial Alzheimer disease. Researchers have identified three genes that cause early-onset familial Alzheimer disease, the amyloid beta precursor protein (APP) gene, presenilin 1 (PSEN1) gene, and presenilin 2 (PSEN2) gene. In general, most individuals diagnosed as having early-onset Alzheimer disease have had an affected parent.

Early-onset Alzheimer disease is often inherited in an autosomal dominant manner, meaning that the risk to offspring of an individual with early-onset familial Alzheimer disease is 50% if a mutation is found in APP, PSEN1, or PSEN2. Occasionally, neither parent is affected, but a second-degree relative (e.g., an uncle, aunt and/or grandparent) has or had early-onset Alzheimer disease.

You can read a comprehensive review of early-onset Alzheimer disease on the GeneReviews Web site.
Last updated: 7/5/2013

What is late-onset Alzheimer disease and how is it inherited?

Late-onset Alzheimer disease is a form of Alzheimer disease that begins to affect people after the age of 65. The genetic causes of late-onset Alzheimer disease are less clear. No gene that definitely causes the condition has been identified. However, a gene called APOE has been studied extensively as a risk factor for the disease. In particular, one form (or allele) of this gene seems to increase an individual's risk for developing type 2 Alzheimer disease. [1]
Last updated: 7/5/2013

References
  1. Alzheimer Disease Overview. GeneReviews. http://www.ncbi.nlm.nih.gov/books/NBK1161/. Accessed 1/25/2008.


Other Names for this Disease
  • FAD
  • Familial Alzheimer disease
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.