Scientists have known for a long time that many of our physical qualities are predetermined by our genes. This includes eye color, height, and even whether someone has dimples.

Now, scientists are discovering that some gene mutations may lead to serious health conditions, including high cholesterol, which can cause other health conditions.

Recent research suggests that some people may be more likely to have high cholesterol based on a certain genetic mutation called the APOE4 gene.

The APOE gene makes the protein apolipoprotein E (Apo E). Apo E is involved in the production, transport, and use of cholesterol in the body. There are three different common variations of the APOE gene: E2, E3, and E4.

Human beings have two sets of every gene — one pair for every gene within their cells. This means that there are 6 possible combinations of the APOE gene: (E2/E2, E2/E3, E2/E4, E3/E3, E3/E4, and E4/E4)

The E3/E3 combination is the most common one and is found in approximately 60% of people. This is associated with normal blood cholesterol levels.

The APOE4 gene variant is most common in Africans and African Americans but can be found in varying degrees in ethnic groups across the globe.

People with the APOE4 gene variant have a greater chance of developing Alzheimer’s and heart disease. If you have two copies of APOE4, experts say the risk of heart disease is increased by 45% and the risk of Alzheimer’s disease is 12 times higher.

Recent research from MIT indicates that choline supplements may be helpful in reversing the effect the APOE4 gene has on the brain’s ability to metabolize lipids and respond to stress.

A low fat, high carb diet may also help to reduce some of the health risks associated with high ) cholesterol levels and the APOE4 gene. (A low carb, high fat diet is recommended for those with the APOE2 gene.)

The different variations of the APOE gene make people more susceptible to different levels of blood cholesterol based on the fat in their diet.

APOE2 genes are generally associated with low LDL levels. On the other hand, the E4 variant is characterized by faster cholesterol metabolism. This typically results in higher LDL and total cholesterol levels at even low body mass indexes for those with APOE4 genes.

People with an E4/E4 gene combo are at the greatest risk for high LDL levels. A person who carries an E2/E4 gene combination is typically expected to be similar to an E3/E3. (This would equate to normal expected cholesterol levels.) A person with an E3/E4 gene mix has a risk level that falls between an E3/E3 and E4/E4.

High amounts of LDL is a major risk factor for cardiovascular disease. LDL cholesterol is sometimes referred to as “bad” cholesterol because it can build up in the walls of arteries. This can increase blood pressure and raise a person’s chance of heart attack, stroke, and atherosclerosis.

It’s important to note that even without APOE4 genes, an individual can find themselves with high LDL levels. Some examples of other risk factors that can lead to high cholesterol include smoking, alcohol consumption, and a lack of exercise.

Familial hypercholesterolemia (FH) is an inherited condition that results in high LDL and total cholesterol levels. There’s currently genetic testing available for FH, but it has limitations.

For example, some mutations that may cause FH are still unknown, which means that FH may not always be revealed through genetic testing. Additionally, most people with high cholesterol don’t have FH, so genetic testing based solely on high cholesterol levels may not be helpful.

Genetic testing isn’t required for an FH diagnosis. Your cholesterol levels, family health history, and physical signs may be enough for an FH diagnosis. If you believe that you’re at risk for FH, you may choose to undergo genetic testing though.

Genetic testing looks at the LDLR, APOB, and PCSK9 genes to see if there are any known mutations that may indicate FH.

If an FH mutation is known to run in your family, you should be tested for that mutation. If no specific FH mutation has been identified in your family yet, you can still be tested, but the results may be uninformative.

Even if you don’t have an FH-causing mutation, you can still be at risk for heart disease from other factors, including high cholesterol. Your cholesterol levels can be checked through a blood test called a lipid panel.

The APOE gene makes a protein that impacts the production and treatment of cholesterol in the body.

There are three common variations of the APOE gene. The APOE4 gene variation can mean that you’re more likely to find yourself with high LCD levels. People with the APOE4 gene are also at an increased risk for Alzheimer’s disease and heart disease.

If you have two copies of the APOE4 in your genetics, you may wish to speak with your doctor or a geneticist about the potential risks and ways to reduce the possibility of serious health conditions.