What are cardiovascular diseases?
Cardiovascular diseases (CVD) include heart attack and stroke, and maintaining normal cholesterol levels is essential for the prevention of CVD. LDL-cholesterol is often referred to as the “bad” cholesterol. It collects in the walls of your blood vessels, where it can cause blockages and scarring known as atherosclerosis. Increased LDL-cholesterol levels put you at greater risk for CVD.

Other contributing factors to CVD include elevated triglycerides (the main form of storage fat in our body) and high levels of other low-density lipoproteins (e.g. beta-very low-density lipoproteins). Hyperlipoproteinemia type III is one disease characterized by elevated triglycerides and beta-very low-density lipoproteins and is associated with an early onset of peripheral vascular disease and CVD.

How does the APOE gene affect cardiovascular health?
The APOE gene encodes Apolipoprotein E (ApoE), a protein involved in the production, delivery, and utilization of cholesterol in the body. There are several different versions or alleles of the APOE gene, and the three most common alleles are known as e2, e3 and e4. Each of these alleles produce a slightly different version of the ApoE protein.

• e3: The most common allele worldwide and is viewed as the neutral allele, with no increased or decreased risk of cardiovascular disease
• e4: Associated with an increased risk of high LDL-cholesterol levels and atherosclerosis
• e2: Associated with lower LDL-cholesterol levels in the blood, but increased risk of high blood sugar and hyperlipoproteinemia type III, leading to a higher risk of cardiovascular disease

How does the APOE gene influence response to diet and statins?
Different versions of the APOE gene will also affect how a person responds to diet and statins (cholesterol-lowering drugs). A low-fat diet is recommended for individuals with the e3/e4 and e4/e4 genotypes, as these individuals are not able to metabolize fats very effectively. These individuals do not respond very well to statins.

Individuals with the e2/e2 or e2/e3 genotype are able to metabolize fats more efficiently but have less effective metabolism of carbohydrates. These individuals have a better response to statins.