I originally wrote this article as a guest post for RebelHealthTribe.com.
**NOTE** I no longer recommend the 23andme DNA test when used for learning about your genetic predispositions for health related things IF the kit was purchased after August 2017, when they changed to version 5 chips. I now recommend this DNA spit test kit that comes with a personalized interpretation video of your specific genome.**
MTHFR is the buzzword lately. You’ve probably heard of it. Maybe you’ve even burrowed deep into rabbit holes in an attempt to learn more. Lots of people are getting genetic testing done because it’s a main “jumping off” point for learning about epigenetics, and many medical doctors are now providing testing.
Before I get into the topic of MTHFR, let’s talk about salivary genetic testing and why someone might want to get it done.
What Kind of Info Does the Genetic Testing Provide?
One small tube of saliva can be filled with a wealth of genetic information. Because 23andme is the service that I use personally and professionally, I’m going to write in reference to that (and receive no compensation from them for writing this). It does not require going through a doctor or practitioner at all! Just receive your kit, spit in the tube, send it away and wait…and wait. Waiting the eternity of weeks for my results made me feel like a kid excited about Christmas morning.
Like most other people, I opted to get the testing done to see if I “have” MTHFR, but also was excited to learn about my ancestry, since my mom was adopted.
My ancestry information came first, about 4-6 weeks after mailing my spit. This info was super cool because I now know I am precisely 48% Japanese. My dad is an All-American Mutt with ancestors from northern Europe and the results also confirmed which parts. There was way more information about my lineage and ancestral migratory path than I was able to read at any given time (and still have plenty more to read).
Because I opted in to receive emails when someone new has DNA in common with me, I get emails somewhat regularly that tell me when I have a new relative (most are distant – somewhere around a 6th cousin or more).
So my general takeaway on the ancestry tip is that the info is abundant and interesting.
The Raw Data
A few weeks after my ancestry info arrived, my raw data was finally ready for me! Because the software I currently use was not yet available at the time (this was a few years ago), I uploaded my raw data into a few low-cost services that would interpret a small handful of my genetic SNPs (more on what those are shortly). I did end up having a single copy of one of the MTHFR variants, and the less risky one at that, but I also found out that I had some SNPs on other genes that increased my potential for health risks relating to cardiovascular issues, mental health, need for B12 and a good potential for inflammation.
What is a SNP and How Does Someone Get One?
DNA replicates, we all know that. Sometimes there are errors in coding replication, just like when we are copying a recipe and accidentally put a tsp instead of tbsp. All recipes copied from that erroneous one will have that error unless another mistake is made somewhere down the line. While most of the population has the original “ancestral allele” that has been passed down for generations, the “risk allele” is the variated/defected version that is less common within a population. This is a SNP, or single nucleotide polymorphism (pronounced “snip”).
When someone “has MTHFR” or “has the breast cancer gene,” they mean that they have the SNP that has been linked to increased health risks, and there are thousands of them for all kinds of genes.
So, having a SNP (or for simplicity, a defected copy of a gene) means is that they inherited a defected copy from either one parent (which is called being “heterozygous”) or one copy from each parent (in which case they are “homozygous”). Or they may not have inherited a defect copy from either parent, in which case they’d technically be homozygous for NOT having the SNP. Generally speaking, if someone has a heterozygous SNP, the efficiency of that gene to code for producing an enzyme is reduced by a certain amount. If they have two copies of the SNP (homozygous), the efficiency is reduced even further.
According to Genetics Home Reference, a part of the NIH, “SNPs occur normally throughout a person’s DNA. They occur once in every 300 nucleotides on average, which means there are roughly 10 million SNPs in the human genome.”
Most SNPs have no effect on health or development, but some have proven to impact our health greatly. SNPs can affect our biochemical processes in an almost endless set of ways, for example how we look, what our taste preferences are, or if we are naturally predisposed or resistant to certain diseases.
Again, Genetics Home Reference puts it succinctly, “Researchers have found SNPs that may help predict an individual’s response to certain drugs, susceptibility to environmental factors such as toxins, and risk of developing particular diseases.”
SNPs can be caused by things like replication errors, errors in DNA repair, nutrient deficiencies, toxins and radiation. HOWEVER, just because someone has a SNP does not mean it is doomed to express!! It has been estimated that 80-90% of what determines whether a SNP will express is due to environmental and behavioral factors.
An article in Environmental Health Perspectives states, “The presence of a particular gene or mutation in most cases merely connotes a predisposition to a particular disease process. Whether that genetic potential will eventually manifest as a disease depends on a complex interplay between the human genome and environmental and behavioral factors [like alcohol consumption, all forms of stress, poor nutrient intake, and cigarette smoking]. Although genes are critical for determining function, nutrition modifies the extent to which different genes are expressed and thereby modulates whether individuals attain the potential established by their genetic background.”
Genetic testing interpretation is able to provide information to you about your potential for certain health challenges, it can help to identify the root cause of physical and emotional health problems, and it can help people make more informed decisions about how they want to manage their health care. It does not diagnose or treat any illness or disease.
What is MTHFR? And Why Would Someone Want to Know If They Have It?
Okay, let’s say you’ve done your 23andme test and have determined that you have an MTHFR SNP. There are thousands of genetic SNPs that humans can have, and MTHFR variants are ones that have been widely researched.
MTHFR is a gene that provides coding for the production of an enzyme called methylenetetrahydrofolate reductase (MTHFR). It plays a critical role in the conversion of synthetic folic acid into the bioavailable (useable) form of folate, although it has many other functions.
I just want to stop the bus and make sure to mention that despite what major health publications (and maybe even your doctor) say, folic acid is not naturally found in food! Folic acid is synthetic and found nowhere in nature. Folate is the correct form, which is found in foliage like leafy greens, as well as in eggs, liver and other fruits and vegetables. Folic acid is found in supplements of questionable quality and in refined grains and other fortified foods like cereal and bread … Okay, the bus can proceed.
The common response to having an MTHFR variant is to compensate by taking high doses of folate and avoiding folic acid (I explain why in the next post). While I agree with avoiding folic acid, supplementing with high doses of folate is not the first (or only) step in managing MTHFR and all its “quirks.”
In Part 2 of this post, I’ll dive deeper into MTHFR and methylation, why supplementing with folate for an MTHFR variant right off the bat can backfire, and the proper way to go about it. I’ll also discuss getting your genetic testing done and interpreting the results. I look forward to seeing you again soon!
{End of part 1}