Genotyping and Endocrinology Clinical Services:
Apolipoprotein E (ApoE)__
Polymorphisms in the ApoE gene increases the risk for heart disease, Alzheimer's disease and stroke- three of the four major age related diseases in the western world. These polymorphisms have been implicated in altered lipid transport, heparin binding, lipid binding, receptor binding activities, lipid metabolism, lipoprotein metabolism, cholesterol metabolism, circulation, development, and immune response.
Why Determine SNPs Like ApoE?
Clinical Studies - ApoE is a strong risk factor for heart disease, Alzheimer's disease and stroke. Therefore, analysis of any therapeutic clinical studies testing drugs on these diseases will need to take into account this confounding factor.
Individuals - Testing for and identifying the ApoE e4 allele in individuals may alter treatment options and affect lifestyle options. Determination of the genetic predisposition of an individual helps with disease diagnosis and susceptibility, and better management of disease. For example lifestyle options that limit fat intake and/or promote exercise might offset development of heart disease, stroke and Alzheimer’s disease. Other reasons to test for ApoE include:
1. The ApoE e4 polymorphism is a major risk factor for Alzheimer's disease. Patients who develope Alzheimer's AND have one or more ApoE e4 copies of the e4 gene are more likely to have Alzheimer’s disease.
2. ApoE polymorphism determination can be used as a follow-up test for high cholesterol and triglyceride levels for determination of risk of heart disease, Alzheimer’s disease and stroke.
3. Patients with ApoE e2/e2 alleles are at a higher risk of premature vascular disease. ApoE e2/e2 is diagnostic of Type III hyperlipoproteinemia (although diagnosis must be made in conjunction with other test results and the patient's clinical history).
4. Patients who have the ApoE e4/e4 alleles are more likely to develop atherosclerosis.