Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
18 Dec

Should You Get Your Genome Sequenced?

Genetic Disease ConceptEarlier this year, I explored the “evolution” of human dietary requirements in the last 10,000 years by examining some of the SNPs – single nucleotide polymorphisms, or variations in genetic sequences – that relate to diet and nutrition. I concluded that while certain genetic changes to the way we process certain foods have arisen in certain populations, for the most part we’re still best off eating from an ancestral, Primal spread of animals, sea creatures, and plant life. Nothing has changed on that front in my mind, but people are still understandably curious about their genetic predispositions toward various conditions, and, with the recent reduction in price for SNP sequencing from 23andMe (to $99 with no subscriptions required), as well as slightly more affordable full-on genome sequencing (~$1000) on the not so distant horizon, it’s easier than ever to actually do it.

But should you?

I definitely don’t think everyone should do it. It’s the least expensive it’s ever been, but there are other factors to consider before making your choice and taking the plunge.

The stress of “knowing.”

What if you were to do it and the results came back showing you carried the allele for an increased risk of heart attack? Would you go on statins? Would you change your diet? Would you freak out and bounce from veganism to Primal to fruitarian? You might not even change anything about your lifestyle, continuing to eat healthy and exercise regularly and get plenty of sleep only, but with the addition of a nice helping of useless stress to go along with it and complicate matters. And the added stress can make the threat of disease even higher.

Laymen misinterpreting data.

“The gene for” is a scary phrase that’s permeated our culture. We worry about the gene for breast cancer, the gene for Alzheimer’s, the gene for baldness, and so on, but the reality of genetics is much more complex. Most of us aren’t equipped to evaluate the data we get from these services, and trying to do so may get us into trouble.

An excess of data and paucity of interpretation.

We know a good amount, but the field of personal genomics is still in its infancy. What if you come up with a particular SNP that has successfully predicted a disease in several studies – you’re gonna get that disease, right? No. In all those studies that showed a connection, not every single person with that SNP got the disease. There could be other, unknown alleles that interact with the original “bad” SNP, countering it and rendering it null. There could be lifestyle factors that affect the expression of the gene variant, intensifying or negating it. We just don’t know yet. And in case you thought we just need more data to get it right, getting more elaborate sequencing may confuse things even more, at least until the experts are better versed in analyzing the results.

Inaccurate results.

They’re still working out the kinks on this stuff, as one journalist who tried out several different competing genome sequencing services and got wildly varying results discovered. Or how when Razib Khan, a huge proponent of 23andMe and other sequencing services, used the ancestry feature set and found out that while he was 40% Asian, his daughter was only 8% Asian. He was able to adjust the parameters and get it figured out, but the average consumer may be misled.

That said, it’s true that the more people get sequenced, the more data the experts will have to draw on and learn from. Thus, doing it could help “the greater good,” if you care about that sort of thing. I actually think that’s a legit reason to get the sequencing if you’re going to do it, but it may not be enough to justify it in your eyes (and wallet).

If you’re a chronic worrier, a person who assumes the worst and runs to Google whenever you get an odd symptom (remember, everything’s cancer on Google), use caution. Sequencing your genome or getting an SNP analysis could ease your worry and show you that you’ve got nothing going on, or it could kick start your mania and make things even worse. If you thought Primal blogs and message boards get unnecessarily arcane, check out the level of analysis on personal genome sites! I was tempted to write “overanalysis” back there, but did not, because the complexities of genome research are such that detailed analysis is often required rather than overkill. And that’s my point: if you don’t have the time for it – if you’ve already got a busy schedule and heaping more work on top of it would only add stress – it’s probably not worth it.

If you’re the curious sort, a person who wants to know how much Neanderthal blood you’ve got and whether your earwax is moist or dry, go for it. You’ll likely find some interesting data to play around with. If you can afford it, you’ll probably be glad you got sequenced.

If you’re already doing everything right, wowing the doctors with your health markers, losing weight if you have some to lose, improving in the gym, and generally just feeling fantastic, you probably don’t need it. You might learn a few things, but it won’t all of a sudden invalidate your current healthy habits.

If you’re the type who needs a kick in the pants to get going and get healthy, if you’ve been lagging and feeling crummy, if you need the fear of the genome to get you moving in the right direction, getting sequenced might be worth it. 

Gene expression is still king. Just because you got your results back and have the SNP “for” a particular condition doesn’t mean you’re going to get it. You might be more likely to get it provided you engage in certain behaviors. However, many of these behaviors are things you are already (or should be) avoiding: sitting inside watching TV all day, eating processed refined food for all your meals, eating food fried in rancid seed oils, failing to exercise or move your body on a daily basis, being socially isolated, never experiencing nature, failing to use your brain, and rarely laughing or smiling. Sure, a few genetic states might conflict with the general Primal advice:

  • Like a sunlight allergy; if you’re allergic to the sun, you’ll know it because it might feel like “hot wax” on your bare skin.
  • Folks with hereditary hemochromatosis may absorb and store excessive amounts of iron, which can increase inflammation and lead to various illnesses. Testing ferritin levels, giving blood and limiting dietary iron – or consuming iron-chelating coffee, tea, and red wine with iron-rich foods – are good moves for people concerned about hemochromatosis.
  • Some people carry an allele that impairs their ability to utilize and convert folic acid, but that just means you should be getting your folate from leafy greens and organ meats rather than folic acid supplements – which you should be doing anyway.

Overall, I like the potential of genetic sequencing, but it’s not quite there yet. Family history trumps genetic data, at least for now. Ask Grandma about her parents and parents’ parents, look at old family photos, explore causes of death for your relatives – these will give you a nice general picture of the state of your genetic susceptibility to various diseases. It’s not as “exact” as genome sequencing, but it’s much easier to analyze.

In the end, whatever your genome has to say about you, the basics are always going to work out. Eating plants and animals, walking a lot, lifting heavy stuff, sprinting, and all the other usual Primal Blueprint advice is never going out of style. For that reason, I’m not very interested in getting my genome or SNPs sequenced. Over the course of almost sixty years, I’ve got a pretty good handle on what makes me tick, what makes me feel like crap, and what makes me healthy, happy, strong, fit, productive, and energetic. If, for argument’s sake, I discovered that whatever I’m currently doing to feel all those awesome things would somehow negatively interact with a random gene mutation, I still wouldn’t change a thing.

But I sure as heck might worry more.

Thanks for reading, folks. I’d love to hear from you, now. Have you had your genetics sequenced? Are you interested?

You want comments? We got comments:

Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. My wife and I did 23andMe to prior to having kids just to check for shared carrier genes.

    On that front, our kids would be very safe from any disease.

    But I came out with a hugely increased chance of DVTs. This actually got my doctor to write a note for a sit/stand desk at my work which is awesome.

    With the knowledge I gained from 23andMe it was that much more motivation to adopt primal living.

    Kevin wrote on December 20th, 2012
  2. I’m hoping to get an official diagnosis for a mental disorder then live the rest of my life thriving on a disability pension.

    Animanarchy wrote on January 2nd, 2013
  3. I’m coming in a little late here – I recently purchased a kit and received my results from 23andme and I’m not sorry I did it. As stated, there are lots of holes to be filled, however what it did tell me is very accurate. Much of the health I know about myself. I didn’t learn anything shocking or that I’m dwelling on, and I also know that while I may not be susceptible to certain diseases, it doesn’t mean that I’m free and clear of those diseases should I live my life in a way that would cause a condition to crop up (like, I may not have the Alzheimer’s gene, but that doesn’t mean that I can go around beating myself into concussion after concussion and expect that I won’t get Alzheimer’s). If nothing else, I had hours of entertainment in looking at my results (yeah, I read every little detail…it was relevant – I was taking a genetics class at the time)

    Kelly wrote on January 2nd, 2013

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