Genetic Testing: Health Benefits & Methods
Genetic testing is an oft-derided American pastime, but there’s a lot more to it than finding out about your ancestry!
Note: because there are relatively few companies offering health-related genetic testing services, and we are talking about the benefits of those services, some of this main feature may seem like an advert.
It’s not; none of those companies are sponsoring us, and if any of them become a sponsor at some point, we’ll make it clear and put it in the clearly-marked sponsor segment.
As ever, our only goal here is to provide science-backed information, to enable you to make your own, well-informed, decisions.
Health genomics & genetic testing
The basic goal of health genomics and genetic testing is to learn:
- What genetic conditions you have
- Clearcut genetic conditions, such as Fragile X syndrome, or Huntington’s disease
- What genetic predispositions you have
- Such as an increased/decreased risk for various kinds of cancer, diabetes, heart conditions, and so forth
- What genetic traits you have
- These may range from “blue eyes” to “superathlete muscle type”
- More specifically, pharmacogenomic information
- For example, “fast caffeine metabolizer” or “clopidogrel (Plavix) non-responder” (i.e., that drug simply will not work for you)
Wait, what’s the difference between health genomics and genetic testing?
- Health genomics is the science of how our genes affect our health.
- Genetic testing can be broadly defined as the means of finding out which genes we have.
A quick snippet…
More specifically, a lot of these services look at which single nucleotide polymorphisms (SNPs, pronounced “snips”) we have. While we share almost all of our DNA with each other (and indeed, with most vertebrates), our polymorphisms are the bits that differ, and are the bits that, genetically speaking, make us different.
So, by looking just at the SNPs, it means we “only” need to look at about 3,000,000 DNA positions, and not our entire genome. For perspective, those 3,000,000 DNA positions make up about 0.1% of our whole genome, so without focusing on SNPs, the task would be 1000x harder.
For example, the kind of information that this sort of testing may give you, includes (to look at some “popular” SNPs):
- rs53576 in the oxytocin receptor influences social behavior and personality
- rs7412 and rs429358 can raise the risk of Alzheimer’s disease by more than 10x
- rs6152 can influence baldness
- rs333 resistance to HIV
- rs1800497 in a dopamine receptor may influence the sense of pleasure
- rs1805007 determines red hair and sensitivity to anesthetics
- rs9939609 triggers obesity and type-2 diabetes
- rs662799 prevents weight gain from high fat diets
- rs12255372 linked to type-2 diabetes and breast cancer
- rs1799971 makes alcohol cravings stronger
- rs17822931 determines earwax, sweating and body odor
- rs1333049 coronary heart disease
- rs1051730 and rs3750344 nicotine dependence
- rs4988235 lactose intolerance
(You can learn about these and more than 100,000 other SNPs at SNPedia.com)
I don’t know what SNPs I have, and am disinclined to look them up one by one!
The first step to knowing, is to get your DNA out of your body and into a genetic testing service. This is usually done by saliva or blood sample. This writer got hers done many years ago by 23andMe and was very happy with that service, but there are plenty of other options.
Healthline did an independent review of the most popular companies, so you might like to check out:
Healthline: Best DNA Testing Kits of 2023
Those companies will give you some basic information, such as “6x higher breast cancer risk” or “3x lower age-related macular degeneration risk” etc.
However, to really get bang-for-buck, what you want to do next is:
- Get your raw genetic data (the companies above should provide it); this will probably look like a big text file full of As, Cs, Gs, and Ts, but it make take another form.
- Upload it to Promethease. When this writer got hers done , the cost was $2; that price has now gone up to a whopping $12.
- You will then get a report that will cross-reference your data with everything known about SNPs, and give a supremely comprehensive, readable-to-the-human-eye, explanation of what it all means for you—from much more specific health risk prognostics, to more trivial things like whether you can roll your tongue or smell decomposed asparagus metabolites in urine.
A note on privacy: anything you upload to Promethease will be anonymized, and/but in doing so, you consent to it going into the grand scientific open-source bank of “things we know about the human genome”, and thus contribute to the overall sample size of genetic data.
In our opinion, it means you’re doing your bit for science, without personal risk. But your opinion may differ, and that’s your decision to make.
Lastly, on the pros and cons of pharmacogenetic testing specifically:
