Cardiovascular Disease (ApoE) DNA Test
Fee Schedule for Year 2019
|Test Type||Testing Time||Fee|
|Cardiovascular Disease (ApoE) DNA Test||2 to 4 weeks||$3820Order Kit|
All orders received before 2pm are shipped out the same business day. All orders received after 2pm or on weekends or holidays are shipped out the following business day. 24/7 online status check and account management available for all tests.
What are cardiovascular diseases?
Cardiovascular diseases (CVD) include many heart and blood vessel problems. Heart attacks and strokes are often caused by atherosclerosis, which is when fatty substances build up in blood vessels leading to plaque formation. These plaques can narrow or block blood vessels, reducing blood flow to certain tissues.
A blocked vessel in an extremity like the arm or legs it leads severe pain and cramping in the affected area. Strokes result from blocked vessles in the brain. If the blockage or narrowing is in the heart tissue itself, a heart attack can occur. Other types of CVD include heart failure (when the heart is not pumping enough blood around the body), arrhythmia (abnormal heart beat) and stenosis (when heart valves do not function correctly).
What causes cardiovascular diseases?
Blood cholesterol levels is one risk factor contributing to CVD. If there is too much LDL-cholesterol (“bad” cholesterol) in the bloodstream, it accumulates as fatty deposits,. LDL- cholesterol stimulates extra cell growth within the blood vessels, leading to atherosclerotic plaques.
Many genetic and environmental factors can contribute to elevated LDL-cholesterol levels. Genetic variants of the APOE, LDLR, APOB and PCSK9 genes are all linked to increasing the risk of elevated LDL-cholesterol and CVD. Other factors that can affect LDL-cholesterol levels include gender (males generally have higher levels), age (older people have higher levels), excess alcohol consumption, high fat diet, low physical activity and obesity.
Variations in the APOE gene are also linked to an increased risk of hyperlipoproteinemia type III. This disorder lowers the metabolism of cholesterol and triglycerides in the blood, leading to cardiovascular problems.
How is APOE involved in cardiovascular disease?
The APOE gene encodes Apolipoprotein E, a protein involved in the production, delivery and utlization of cholesterol in the body. There are three common forms or alleles of APOE – e2, e3 and e4.
We inherit two copies of the APOE gene- one from each parent. This results in six possible combinations for APOE: e2/e2, e3/e3, e4/e4, e2/e3, e2/e4 or e3/e4.
The e3 allele is the most common allele worldwide and is viewed as the neutral allele, with no increased or decreased risk of CVD. The e4 allele is associated with an increased risk of elevated LDL-cholesterol and CVD. The e2 allele does not increase the risk of elevated LDL-cholesterol. However, there is an increased risk of hyperlipoproteinemia type III in individuals with the e2/e2 genotype.
How does APOE genotype influence the response to diet and statins?
Different versions of the APOE gene also affect how a person responds to diet and statins (cholesterol-lowering drugs). People with the e3/e3 and e2/e3 genotypes are likely to respond well to statins. The e2/e2 genotype is also associated with a good reponse to statins, and a low sugar/low carbohydrate diet is also recommended.
Those at a higher risk of elevated LDL-cholesterol (genotypes e3/e4 and e4/e4) do not responsd efficiently to statins. Instead a low-fat diet is recommended for these individuals to effectively lower LDL-cholesterol levels before cardiovascular problems occur.
DNA testing for APOE
A simple DNA test cdetermine which alleles of APOE a person has inherited. There are three alleles, e2, e3 and e4. Each person can inherit two identical alleles or two different alleles of APOE.
- e2/e2 - This genotype is associated with lower LDL-cholesterol levels, but an increased risk for hyperlipoproteinemia type III. A person with this genotype will respond well to statins.
- e2/e3 - This genotype is not associated with an increased risk of elevated LDL-cholesterol. A person with this genotype will respond well to statins.
- e3/e3 - This genotype is not associated with an increased risk of elevated LDL-cholesterol. A person with this genotype will respond well to statins.
- e3/e4 or e4/e4 - These genotypes are associated with an increased risk of CVD, due to elevated LDL-cholesterol levels. People with these genotypes do not respond well to statins but will benefit from a low fat diet.
- e2/e4 - This rare genotype has been the least well studied and results have been conflicting. Some studies indicate that it is associated with an increased risk of elevated LDL-cholesterol levels (due to the presence of the e4 allele). However, other studies indicate that it is associated with a similar neutral phenotype to the e3/e3 genotype.