The ApoE genetic marker (Apolipoprotein E) is one gene responsible for interpreting the likelihood for an individual to develop Alzheimer’s disease. Genetic markers are sequences of DNA that can help link an inherited disease with the responsible genes. In the brain, ApoE is a protein involved in clearing harmful plaques that form around nerve cells. These plaques are a hallmark of Alzheimer’s Disease and consist of damaged proteins called amyloid-β (Aβ) which stick together to form the toxic plaques. There are three possible types of ApoE proteins, called E2, E3 and E4. Individuals will have a total of 2 of these; one from each parent. Each type possesses a different level of risk:
- Individuals with the E2 allele are at the lowest risk for developing Alzheimer’s Disease, because this form of the protein is the most effective at removing Aβ plaques.
- Individuals with the E3 allele are at no increased risk for developing Alzheimer’s Disease.
- Individuals with theE4 allele are at a significantly increased risk for developing Alzheimer’s Disease because this form of the protein is not very effective at removing Aβ plaques.
ApoE 4 does not guarantee that someone will develop Alzheimer’s. After learning about an individual’s genetic makeup, we can recommend steps to take to reduce your risk of developing the disease.