What is Alzheimer’s disease?
Alzheimer’s disease (AD) is the leading cause of dementia impacting a growing number of elderly individuals in the aging society including 5.8 million Americans. In most cases, the symptoms appear in their mid-60s or later, and it is estimated that up to 32% of people aged 85 or older have AD. Currently, there is no treatment available to stop or reverse the disease progression. Multiple factors, both genetic and environmental, have been shown to affect the risk of AD. Among them, APOE gene is the strongest genetic risk factor.
To learn more, visit National Institute of Aging Alzheimer’s Disease Fact Sheet.
What is apolipoprotein E?
Apolipoprotein E, also known as apoE, is a protein whose primary function is to carry lipids and cholesterol throughout the body. It is encoded by the APOE gene and each person carries two copies of APOE. This gene exists in three versions (APOE2, APOE3 and APOE4) that are called alleles. These alleles are associated with different levels of risk in developing late-onset Alzheimer’s disease (AD) with APOE4 confers the greatest risk. Just one copy of APOE4 increases the likelihood of developing AD by 3-4 folds, while carrying two copies increases it by 12 folds. APOE3, the most common allele, is neutral in risk while APOE2, the least common, is protective.
More About Apolipoprotein E
In AD, a number of proteins tend to form clumps called amyloid plaques and tangles that are toxic to brain cells, in particular neurons, ultimately leading to their death. People who carry APOE4 (carriers) have been shown to have earlier accumulation of amyloid and onset of AD. The mechanisms by which different apoE isoforms modulate Alzheimer-related pathogenic events are becoming clear but still under investigation.
Highlighted Publications
- Alzheimer’s Risk Factors Age, APOE Genotype, and Sex Drive Distinct Molecular Pathways.
- Association of Klotho-VS Heterozygosity With Risk of Alzheimer Disease in Individuals Who Carry APOE4.
- APOE genotype affect risk of becoming severly ill with Coronavirus.
- The relationship between physical activity, apolipoprotein E ?4 carriage, and brain health
- ApoE4 attenuates cortical neuronal activity in young behaving apoE4 rats
- Selective removal of astrocytic APOE4 strongly protects against tau-mediated neurodegeneration and decreases synaptic phagocytosis by microglia