apolipoprotein E

genetics

Also known as: ApoE

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Last updated

July 22, 2026

Quick Summary

Apolipoprotein E (ApoE) is a protein involved in cholesterol transport and metabolism. Genetic variations in the APOE gene, specifically the APOE4 allele, are associated with an increased risk of late-onset Alzheimer disease. The APOE4 variant may lead to increased deposition of amyloid-beta protein in the brain and a higher number of neurofibrillary tangles, which are hallmarks of Alzheimer's pathology. While rare early-onset forms of Alzheimer's are linked to mutations on chromosomes 1, 14, and 21, the APOE gene on chromosome 19 plays a role in the more common late-onset cases.12

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Alzheimer disease
Genetic variants
…gene that directs production of apolipoprotein E (ApoE), which is involved in cholesterol transport, may be a factor in the majority of late-onset Alzheimer cases. There are three forms of this gene—APOE2, APOE3, and APOE4—two of which, APOE3 and APOE4, are associated with an increased risk of disease and influence…
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…gene that directs production of apolipoprotein E (ApoE), which is involved in cholesterol transport, may be a factor in the majority of late-onset Alzheimer cases. There are three forms of this gene—APOE2, APOE3, and APOE4—two of which, APOE3 and APOE4, are associated with an increased risk of disease and influence…
Read More