DNA Testing: An Overview
DNA is often compared to a fingerprint, in that it’s unique to an individual. Your DNA is a code that contains millions of genes, which correspond to various traits, from eye colour to nutrient metabolism. Interestingly, about 99.9% of human DNA is identical. And yet our DNA is still one of the most individual things about us– just based on the 0.01% that differs.
Because we receive genes from our parents and ancestors, genetic testing is a popular way to learn more about where you come from and who you may be related to. It’s also used for a variety of health purposes.
We are learning more about DNA– from the effects of specific genetic mutations to the utility of genomic testing– every day.
In the 1980s, researchers began to identify specific genetic mutations that could lead to genetic conditions like cystic fibrosis. The mapping of the genome has since become a massive field, and researchers are still uncovering new information and insights about specific gene variations and how they might affect us.
The first wave of genetic testing for medical purposes was to screen for mutations that would put an individual at increased risk of developing a specific medical condition (for example, a type of cancer that a family member may have had). This type of testing does not tell you whether or not you have a condition, nor does it tell you whether or not you will develop it: genetic testing is probabilistic, and serves in this case as a potential warning sign.
This can be helpful, as it can prompt you to take action in order to mitigate your risk of developing the disease in question.
We have now entered the age of at-home genetic testing, and a wide range of options are available that use our DNA to look more broadly at factors that may affect our health, including our ability to metabolize certain nutrients or to clear out toxins.
DNA testing is a key component of what many are referring to as “precision medicine” or “personalized medicine”– a treatment approach that is customized based on an individual’s unique needs, including genetic makeup.
Types of DNA Tests
When it comes to genetic testing, options abound. In all cases, a sample is collected (this is generally done with a cheek swab), and the DNA from the sample is compared with “normal” DNA, in order to identify any changes or variations. Where DNA tests differ is in which genes they look at, and why.
While more traditional DNA tests are generally looking for variations and mutations in specific genes related to the risk of a particular disease, newer lifestyle tests are often looking at a wide range of genes, designed to give you a larger scale picture of your genetic makeup.
These tests can tell you whether you might benefit from a diet higher in healthy fats, how quickly you metabolize things like caffeine, how your body is likely to respond to certain kinds of exercise, and whether you may have difficulty absorbing or processing certain nutrients, among many other things.
DNA testing can uncover genetic variations linked to neurotransmitter imbalances, intolerances to certain foods like gluten, impaired methylation, detoxification, and mood. There are also certain genetic mutations that are associated with an increased likelihood of histamine intolerance.
All of this information, combined with other factors, can help you to put together an individualized nutrition and lifestyle plan.
Another area of increasing research and interest is pharmacogenomics, which is the study of how an individual’s genes affect their response to certain kinds of medications and drugs.
Interpreting DNA Test Results
DNA test results can be alarming, overwhelming, and even contradictory at first glance. In fact, in the early days of 23andMe, they were temporarily shut down by the FDA– until they could prove that consumers could understand the results of their tests.
It’s generally a good idea to be working with a practitioner who can walk you through what your results really mean (and what they don’t mean), and help you to identify a practical action plan using what you’ve learned about your genome.
Especially when you are looking at the results of a general health and lifestyle DNA test, it is not uncommon to find contradictions.
For example, you may have one genetic variation that is associated with an enhanced ability to metabolize caffeine, and another that is associated with a reduced ability to detoxify it. So, on the one hand, you may be told that you don’t have to worry too much about limiting your coffee consumption, and on the other hand, you’re told that you do!
Remember that a DNA nutrition and lifestyle test can’t tell you anything about how what you’re doing (like drinking coffee) is actually affecting you now. What it can tell you is the foundation that you’re working with, and how your body might be expected to respond or react to various things based on what we currently know about the human genome.
Having a genetic predisposition to a disease does not mean that you will develop it, and by the same token, not having a predisposition does not preclude you from developing the condition. Many, if not most, of the factors that contribute to the majority of chronic illnesses are modifiable.
What genetic testing for disease risk can do is arm you with the knowledge you need to make lifestyle choices that will help to mitigate your risk and enhance your overall health. It is when combining what you know about your genetics with what you know about and can control within your environment that you can really start to get somewhere.
The study of the interaction between our genes and our environment is called epigenetics, and it is a fundamental aspect of integrative medicine.
You can’t control your genes, but you can make changes to your environment: and the more you understand about your genes, perhaps, the better equipped you are to make educated decisions when it comes to the controllable environmental factors.
Environmental factors can include diet, alcohol intake, exposure to toxins, hormonal imbalances, and nutrient deficiencies.
When it comes to lifestyle genetic testing, the same rule generally holds: it’s a little “heads up” from your genetic code that will hopefully prompt you to take action when it comes to your diet and lifestyle, and help you to better understand the foundation you’re working with.
Our Experience with the DNA Labs Love My Health Test
When interpreted properly, the data from lifestyle DNA test kits can be useful, actionable, and empowering.
Our whole team at Markham Integrative Medicine recently swabbed our cheeks for the “Love My Health” DNA lifestyle test from Canadian company DNA Labs. We were given comprehensive reports– available as printable documents or to view interactively online– filled with insights into our genes, and actionable items.
DNA Labs sorts results into categories, including specific nutrient needs, sensitivities, mental wellness, detox, physical fitness, and hormonal health. The Love My Health test tells you whether or not you have a genetic predisposition to lactose or gluten intolerance, and it looks at genetic variations related to histamine intolerance. They show you everything they’re testing for, and tell you whether or not you have one or more genetic variations related to each item. If you do, they tell you what actions you can take to address the susceptibility.
They refer to their genetic report as your very own “owner’s manual”.
So, how was our experience? We all found it fascinating to learn about our genes, and found that much of what this particular test looked at was relevant to our everyday lives. There were definitely a few “aha!” moments for each of us!
We did come across a few contradictions (which is normal, as discussed above), and could see the potential for confusion. Again, genetic lifestyle test results need to be taken with a grain of salt, and interpreted with caution and understanding. But when done right, they do have the potential to help us learn about our own bodies, and prompt us to take action.
For more personalized guidance, request a consultation with Dr. John Gannage, MD.
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