Genetic testing
If you’re interested in assessing your risk of developing a specific disease, genetic testing can be a useful tool. When it comes to assessing your risk of contracting a given disease, there are 2 main things to take into account:
- Genetic risk factors: what you start with in life, the cards you are dealt with.
- Lifestyle: factors that you encounter during your life, how you play the cards and how the game goes.
In this article, we’ll focus on genetic risk factors and how genetic testing can help you understand your risk for certain conditions.
One common reason for genetic testing is to check for mutations in genes associated with specific diseases. For example, if you’re a female and there’s a history of breast cancer in your family, you might want to check if you have the same genes, you are aware of a potential risk factor, and want to confirm or infirm the hypothesis you have it. And if there is no history of breast cancer, then checking that you don’t have the carrier genes makes also perfect sense. Personally, my main reason for doing this test was to check if I am a carrier of ApoE4, a mutation of the ApoE gene that increases your chance of developing Alzheimer’s by 200–250% if you have one copy and by 300–500% if you have both (reference). Losing my mind and my memory is my greatest fear.
Understand me, it’s not because you are not a carrier of a specific diseases’ gene mutation that you will never get the disease, but it means there is no urgent need to focus on this specific disease. On the contrary, if you found out you are a carrier of a gene mutation increasing your chance of developing disease X then you might want to tackle this issue first, learning more about disease X, doing more tests etc. The purpose of this test is to eliminate some aggravating risk factors really.
Most DNA genetic testing kits are focused on ancestry — while this is fun and interesting, it’s not what I was looking for. The most complete DNA genetic testing kit I found is from 23 and me (This is a sponsored link that gives you 10% off by using this referral link).
Below is an excerpt from my results:
As you can see there is no variant detected for Alzheimer’s, which is quite good. It doesn’t mean I am not going to develop Alzheimer’s but at least I am starting with not-screwed-up odds :).
However, I have an increased risk of developing AMD and losing my vision. If we look in detail:
First, they give a brief explanation of what AMD is, then they tell me how many copies of the genetic variant they found and below they give more explanations as to what variants were tested, the limitations of the test etc.
OK, here is more info about the test results, they found two copies of the Y402H variant, I got one from each of my parents. I actually got my family to do the same test and my brother and I are the only ones with a copy of both variants, my sister doesn’t have a single one and both my parents have one.
Then a list of the lifestyle factors that influence the chances of developing AMD with some text about each factor. This is a lot of blabla and if you are at risk for a given disease, I strongly recommend you do your own research and talk with your doctor to see how you can tackle that issue.
A complete list of all the tests can be found here.
You can also complement the 23 and me test by taking a comprehensive report from Dr. Rhonda Patrick. I did it and here are a few interesting findings:
So my genotype (rs17300539(G;G)) is “associated with lower ADIPOQ and higher risk for obesity”, nice… This gives me some guidance as to what to pay attention to in my lifestyle. At least I am 26 years old, 1.85m and 70kgs with <5% body fat, which is quite a good starting point in terms of obesity, but still I need to keep an eye on that.
Another very interesting one:
So naturally, genetically even, I have a vitamin D deficiency. Let’s check with my blood tests:
In 2019, I did not supplement in vitamin D and I took a vitamin D test, I was at 29 ng/L which is under the lower bound of the recommended range (which is often too low, as based on the average population, and the average population is not really healthy :) ). Ok, I live in London, so grey weather and less sun but still, I go out every day and I frequently spend weekends and holidays in Southern Europe, so lifestyle is not the only explication here. I then started to supplement and did further tests and you can see I reached 44.8 ng/L in September last year. It’s not yet optimal but should soon be I hope.
This example is to show you that genetic testing is not only good to detect predispositions to certain diseases but also predispositions to other health-related metabolism issues.
As for my greatest fear, Alzheimer’s:
I actually have lower risk of getting Alzheimer's, 40% lower! Also, the bit about alcohol consumption comforts me into my daily red wine glass haha. As much as having an increased genetic likelihood of getting a certain disease doesn’t mean you will get it; having a lower risk of getting Alzheimer’s doesn’t mean I won’t get Alzheimer’s, I still need to be careful and to train my memory daily (which is why I always learn a new language).
Also what I like is that in this report, they highlight the studies used and give links to resources and studies. And the studies they linked have statistically significant results (studies involving thousands of individuals and not just 10 as so many research papers do… I shall write about that. In the meantime read that article on the subject, it’s very interesting).
Whether you go with 23andme or another genetic testing provider, I think it’s a good thing to look at your genetic risk factors before writing down a detailed health plan spanning several years, so that you know what you might want to focus on first.
As always, thanks for reading and don’t hesitate to ask me questions in the comments or to suggest ideas for articles!
