Genes and early onset Alzheimer’s
The genes you inherit influence your risk of getting Alzheimer’s1
Family history of Alzheimer’s is a well-known risk factor for the disease. If a close family member developed late-onset Alzheimer’s (symptoms appear after age 65), you may have a greater chance of developing it as well.
The risk of developing early onset Alzheimer’s (symptoms appear before age 65) is even more closely related to family genes than late-onset Alzheimer’s. Early onset Alzheimer’s can be caused by mutations in one of three genes. Genes are pieces of chemical information that we get from our parents. They help determine many of our physical and other traits.
About the gene mutations1-3
Gene mutations that result in early onset Alzheimer’s are extremely rare, making up fewer than 1 in 1,000 cases of the disease overall. However, children of people who have one of these three gene mutations have about a 50-50 chance of inheriting a mutation that causes Alzheimer’s. All three of these mutations can lead to increased production of plaques in brain cells, which is an important characteristic in Alzheimer’s disease:
- The APP gene on chromosome 21 – More than 80 known families worldwide have mutations in this gene
- The PSEN-1 gene on chromosome 14 – About 400 known families worldwide have this mutation, which causes about half of all early onset Alzheimer’s
- The PSEN-2 gene on chromosome 14 – This mutation is much rarer than the other two, affecting only about a dozen known families (mainly in the United States)
If two or more of your close family members (parents or siblings) develop early onset Alzheimer’s, you should see your doctor, who can set up genetic testing to see if you have one of these mutations.
One family helps further research for early onset Alzheimer’s4
The DeMoe family from North Dakota has one of the genetic mutations that causes early onset Alzheimer’s. Five of six children carry a mutation that has resulted in early onset Alzheimer’s.
In an effort to help further research on early Alzheimer’s, the DeMoes have bravely participated in studies by the University of Pittsburgh that attempt to better understand the disease. They also appeared in a documentary by HBO detailing their inspirational story.
