The apolipoprotein E (APOE) gene encodes a protein involved in the transport of lipids and cholesterol, and its association with Alzheimer’s disease (AD) has been widely studied.The APOE gene has three major types (alleles): APOE ε2, APOE ε 3, and APOE ε4.
Relationship between each type of APOE and Alzheimer’s disease
- APOE ε2
- It is believed to have a protective effect.
- People with APOE ε2 tend to have a decreased risk of Alzheimer’s disease.
- Genotypes e.g. epsilon2/ε2, epsilon2/ε3.
- APOE ε3
- Most common allele (neutral).
- It is not believed to have any particular effect on Alzheimer’s disease risk.
- Genotype e.g. epsilon3/ε3 (common type).
- APOE ε4
- It is a known risk factor for Alzheimer’s disease.
- Having one ε4 allele (ε3/ε4) increases the risk of Alzheimer’s disease by about 2- to 3-fold.
- With two ε4 alleles (ε4/ε4), the risk may increase more than 10-fold.
- Epsilon4 may also accelerate the age of disease onset.
mechanism
The reasons why APOE ε4 increases the risk of Alzheimer’s disease are not fully understood, but the following mechanisms have been proposed
- Abnormal metabolism of amyloid-β: Amyloid-β tends to accumulate in the brain.
- Neuroinflammation: APOE ε4 may promote inflammation.
- Disruption of the blood-brain barrier: leads to decreased neuroprotection.
important point
- Having APOE ε4 does not necessarily mean that you will develop Alzheimer’s disease. Environmental factors (diet, exercise, level of education, etc.) and other genetic factors also play a significant role.
- Conversely, people who do not have APOE ε4 can also develop Alzheimer’s disease.
Clinical Significance
- APOE gene testing may be used to predict an individual’s risk of Alzheimer’s disease, but is not widely recommended for diagnostic purposes at this time.
- APOE genotype is an important indicator in the study of preventive interventions and treatments.
Price
19800 yen (tax included)
