Apolipoprotein E epsilon4 allele frequency in vascular dementia
Yvonne Davidson1, Linda Gibbons, Nitin Purandare
1Clinical Neuroscience Research Group, Greater Manchester Neurosciences Centre, Hope Hospital, Salford, UK.
Dementia and Geriatric Cognitive Disorders
|April 29, 2006
Summary
The apolipoprotein E (APOE) epsilon4 allele significantly increases the risk of developing vascular dementia (VaD). This genetic factor is also linked to Alzheimer's disease (AD).
Area of Science:
- Neuroscience
- Genetics
- Epidemiology
Background:
- Vascular dementia (VaD) and Alzheimer's disease (AD) are major causes of cognitive decline.
- The apolipoprotein E (APOE) gene, particularly the epsilon4 allele, is a known risk factor for AD.
- The role of APOE epsilon4 in VaD risk requires further investigation.
Purpose of the Study:
- To determine if the APOE epsilon4 allele is associated with an increased risk of developing vascular dementia (VaD).
- To compare the APOE epsilon4 allele frequency in VaD patients with those in Alzheimer's disease (AD) patients and control subjects.
Main Methods:
- APOE allele and genotype frequencies were analyzed using PCR.
- The study included 89 patients with possible/probable VaD, 97 patients with possible/probable AD, and 766 control subjects.
- Patient groups were matched for age of disease onset and ethnic background.
Main Results:
- APOE epsilon4 allele frequency was significantly higher in both VaD (p < 0.001) and AD (p < 0.001) patients compared to controls.
- No significant difference in APOE epsilon4 allele frequency was observed between VaD and AD patients.
- The increased frequency of APOE epsilon4 remained significant even when considering only probable VaD and probable AD cases.
Conclusions:
- Possession of the APOE epsilon4 allele is a significant risk factor for vascular dementia (VaD).
- The genetic risk associated with APOE epsilon4 appears to be shared between VaD and AD.
- These findings highlight the importance of APOE genotype in the pathogenesis of dementia.
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