It's In My Genetics : Debunking The DNA Myth

Good or Bad Genes Depends on Context

Genes are often presented as negative or positive depending on disease outcome. But nothing is that simple – certain polymorphisms or SNPs cannot be simply “bad” or “good”, there is only biological context relative to the polymorphisms.

Evolutionarily speaking, every genetic polymorphism that exists must have conveyed evolutionary advantage at some point or it would not exist. For example, in the context of food scarcity, a gene that encourages calorie-dense food consumption may be an advantage. However, in the context of calorie abundance may be more likely to lead to obesity [2] – a situation we increasingly find ourselves in today.

APOE4 is a polymorphism of the APOE gene that carries an increased risk of cardiovascular disease and cognitive decline in western populations. But the exact same polymorphism is protective of cognitive decline and carried no increased risk for heart disease within developing countries [3] or indigenous populations with a high parasitic load. It is clear that genes are only part of the picture– context is everything.

So how can we manage genes?

Epigenetics: The Secret Behind Your Genes

Epigenetics is like the boss of your cells. It tells them what to do and when to do it. Think of DNA like a recipe, it tells your cells how to make you. Epigenetics is like the cook who chooses which recipe to use or not use. And just like a cook can use different recipes to make different meals, epigenetics can make cells into different things, like a muscle cell or a brain cell. Sometimes, the environment can change the way epigenetics works, like if you eat certain foods or if you're around certain things. This can change the way your cells grow and work, which can make you more or less likely to get sick.

Epigenetics is the study of changes in gene activity that do not involve changes to the underlying DNA sequence. These changes can affect how genes are expressed, or turned on and off, in different cells and at different times. Epigenetic mechanisms include DNA methylation, histone modification, and non-coding RNA regulation.

These mechanisms can be influenced by a variety of factors, including environmental exposures, diet, and aging. For example, a great epigenetic mediator is exercise. We know that if you have high-risk genes for obesity, diabetes, or heart disease your risk for all these diseases is reduced by partaking in regular appropriate exercise [4].

So where does nutrition come in?

How Nutrition Affects Epigenetics

Your genetics determine how much of a specific protein, enzyme, lipid, neurotransmitter, receptor, or other molecules are produced and broken down within your body. But, the raw materials you give the body that make this possible, alongside your genetics determines your biochemistry. And how these 2 things interact is Epigenetic expression.

For example, SNP variants of the FADS1 haplotype gene may cause a low conversion of alpha-linoleic acid (ALA, an omega 3 fat found in vegetables or nuts which can’t be used by your body as it is) to eicosapentaenoic acid (EPA, an anti-inflammatory fat the body can use). This means that vegetable sources of ALA alone may not be sufficient for that individual’s omega 3 requirements [5],and animal sources of EPA may need to be included. This person on a vegetarian diet may not thrive but give them the right environment and this gene SNP is no longer a problem.

What can you do?

Eating and Living For Your Genetics

Although there is nothing you can do about your genes – even genes that give the highest risks for disease do not determine outcomes – how you live and eat is more important.

You want to eat a diet that exposes you to all the required macro and micronutrients in the forms and amounts that will enable your genes to best express themselves for health.

This sounds complicated but it needn’t be.

Taking a gene test with a practitioner who is literate in genetic polymorphisms and how this would relate to lifestyle and nutrition is ideal for formulating a plan that may optimise your epigenetics for the rest of your life.