Apolipoprotein E (APOE) is a polymorphic gene with three major allelic variants—ε2, ε3, and ε4—that encodes a lipid transport protein critical for cholesterol metabolism and neuronal repair. The APOE ε4 allele is the strongest known common genetic risk factor for late-onset Alzheimer's disease, with risk increasing in an allele dose-dependent manner. APOE genotyping is used as a risk stratification tool rather than a diagnostic test, as the ε4 allele is neither necessary nor sufficient to cause Alzheimer's disease. The APOE protein plays a central role in lipid homeostasis, facilitating the transport and redistribution of cholesterol and phospholipids among cells, particularly in the central nervous system. In the brain, APOE is primarily produced by astrocytes and influences amyloid-beta clearance, tau pathology, synaptic integrity, and neuroinflammatory responses. The ε4 isoform is less efficient at amyloid-beta clearance and lipid transport compared to ε2 and ε3 isoforms, contributing to increased amyloid plaque accumulation and neurodegeneration.
The APOE gene comes in different versions (called alleles), and the version you inherit can affect your risk of developing Alzheimer's disease later in life. Having one or two copies of the ε4 version raises your risk compared to the most common version (ε3), while the ε2 version may slightly lower risk. However, this is not a test that tells you whether you will or will not get Alzheimer's disease—many people with the higher-risk version never develop it, and many people without it do. This test is most useful when discussed with a genetic counselor or specialist who can help you understand what the results mean for you personally. Knowing your APOE status can sometimes help guide medical decisions, but it should never be interpreted as a definitive prediction of your future health.
When elevated: Presence of one or two APOE ε4 alleles is associated with significantly elevated lifetime risk for late-onset Alzheimer's disease, earlier age of symptom onset, greater amyloid burden on neuroimaging, and potentially faster cognitive decline. APOE ε4 homozygosity (ε4/ε4) confers the highest genetic risk among common variants. ε4 status may also influence cardiovascular risk and response to lipid-lowering therapies. When low: The APOE ε2 allele (particularly ε2/ε2 or ε2/ε3 genotypes) is associated with reduced risk of Alzheimer's disease compared to the ε3/ε3 reference genotype and may be associated with longevity. Absence of the ε4 allele does not eliminate Alzheimer's disease risk, as the majority of cases occur in non-ε4 carriers.
APOE genotype is not directly relevant to athletic performance, training response, or acute recovery. However, for health-conscious athletes focused on long-term brain health and cognitive longevity, APOE status may inform personalized strategies for cardiovascular fitness, cognitive training, and neuroprotective habits—since aerobic exercise, Mediterranean-style nutrition, and cognitive engagement are modifiable factors that may reduce Alzheimer's risk regardless of genetic predisposition.
Turnaround Time
3 days (up to 7 days)
Fasting Required
No
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$300.00
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