This is the 6th out of 13 most popular articles on Skeptical Raptor for the 2016 Year in Review. It’s all about the MTHFR gene mutations, and how overstated it is.
I have a love-hate relationship with the internet. I love that I can Google a question like “who was the second basemen for the Pittsburgh Pirates in the 1960 World Series?” It was Bill Mazeroski for those who care.
Although I think that Wikipedia needs to be used skeptically, it is a wonderful fountain of delicious knowledge. I sometimes just read random articles, and I enjoy the writing, scholarship and knowledge. Some articles, like World War II or the Roman Empire, are truly detailed pieces of scholarship.
But sometimes, the internet does a disservice to mankind, especially when medical information (or really disinformation) is presented as fact. Like vaccines cause autism. No, it doesn’t.
Or that chronic lyme disease actually exists. No it doesn’t.
Or that high fructose corn syrup causes obesity and diabetes. No it doesn’t (except that eating a lot of any sugar might do that).
But the newest one, at least for me, is that MTHFR gene mutations cause nearly every disease known to mankind. Seriously, apparently it is the root of all health evil, and the mutation is caused by…anything.
What is this MTHFR gene?
Methylene tetrahydrofolate reductase (MTHFR) is the rate-limiting enzyme in the methyl cycle, and it is encoded by the MTHFR gene. In other words, the MTHFR gene is responsible for production of an important enzyme.
This enzyme is a critical part of the methionine and folate cycles, which are important to manufacturing methionine, an amino acid which is a fundamental constituent of all proteins on the planet, and folate (or folic acid), which is an essential nutrient.
As obvious in the chart above, the MTHFR gene has a central role in a very complicated biochemical pathways. MTHFR enzyme deficiency (caused by one of several MTHFR gene mutations) leads to two important problems:
- Accumulation of the methionine precursor, homocysteine, which can lead to several types of injury including DNA and vascular damage. People with high homocysteine levels typically respond well to supplementation with vitamins such as B6, B12, and folate or folic acid.
- Lack of folate (folic acid), which leads to several known issues, is easily treated with folate or folic acid. As I’ve discussed in scientifically detailed manner previously, folate and folic acid are simply two forms of the same chemical, indistinguishable by the human biochemistry.
There are several mutations in this gene that have been identified, but in all but a handful (less than 50 cases), residual MTHFR enzyme activity remains, sometimes close to normal levels. To be clear, MTHFR gene mutations are not an on/off proposition–there is a range from almost no MTHFR enzyme activity (very rare) to almost “normal” physiological levels. What matters is not the mutation itself, but the levels of homocysteine or folate, which, again, can be easily diagnosed.
Genetic variation in this gene may influence susceptibility to peripheral artery disease, neural tube defects, Alzheimer’s disease and other forms of dementia, colon cancer, and acute leukemia. Additionally, variations of MTHFR gene mutations have been studied in connection to stroke, high blood pressure and heart disease, as well as bipolar disorder and other conditions. However, these associations have not been established by high quality case-controlled epidemiological studies, there are only some preliminary observations that probably need to be investigated more fully.
One last thing. MTHFR gene mutations are easily diagnosed by high levels of homocysteine and low levels of folate. These conditions can be diagnosed with an inexpensive test (or if you’re willing to waste money by a genetic test, but that’s really not necessary). Of course, those who eat a good diet of foods high in folic acid (which includes a lot of different foods including beer) probably would not notice MTHFR gene mutations.
Now let’s get to the internet myths about the MTHFR gene mutations. This will be loads of fun.
Your child can “catch” a mutation of the MTHFR gene
Absolutely not. One of the several mutations of the gene is generally passed from the genetic material of one of the child’s parents. It is either there or not there (although there is a tiny chance that the mutation might form in the zygote, but that’s awfully rare).
When the fetus is developing, you cannot cause a mutation in one (or even several cells) and that mutation spreads to the whole fetus. That’s not how it works, genes from one cell do not “infect” other cells of the developing fetus. If that kind of genetic transfer were so easy, gene therapy would be the easiest treatment known to medicine.
An infant, child or adult cannot have one of several MTHFR gene mutations spread through the whole body. So, vaccines, gluten, GMO foods, mercury, unfiltered water, fluoride or whatever nonsense known to the internet cannot induce a mutation in a whole body. It is possible that the original MTHFR gene mutations in the parental genotype were originally caused by some environmental factor, but it could have happened many generations before.
Don’t vaccinate a child with MTHFR gene mutations
There is no evidence of this danger, despite widespread internet rumors and myths to the contrary.
There is precisely one published article, published in the Journal of Infectious Diseases nearly 7 years ago, that examined adverse events after a smallpox vaccination being associated with MTHFR gene mutations. What they concluded was:
Editor’s note: they examined three genes, only one of which was associated with MTHFR.
In other words, they found some evidence, but the evidence did not support a conclusion that vaccinating individuals with the MTHFR had increased adverse events.
Moreover, they state that plausibility needs to be established first. There is not much biological plausibility that a vaccine can be associated with the MTHFR enzyme. Though the folate and methionine cycles appear to be complex, they really aren’t, and they are isolated from other biochemical pathways in the body because they occur within cells. And individuals who are being successfully treated for the consequences of MTHFR gene mutations probably wouldn’t be affected by vaccines.
Unless you ascribe to the logical fallacy of the precautionary principle, meaning you need to have evidence that there are no risks whatsoever, then there really is nothing here. But I guess we could waste money, like we did debunking the vaccines cause autism myth.
Quacks and MTHFR gene mutations
One internet quack, Ben Lynch, a naturopathic “doctor” (pure pseudoscience), tries to make claims that MTHFR gene mutations cause a whole host of diseases, using “peer-reviewed” articles. Many of the studies are just plain cherry picking, choosing research that supports his point of view, rather than looking at studies that dispute it.
For example, Mr Lynch (he is not a real doctor, so he doesn’t get that title) claims that one of the MTHFR gene mutations is related to colon cancer. This research can be easily disputed by:
- It is published in a very low impact factor journal, not well cited by other journals.
- It uses a small population (about 300 subjects) in one small area of China. The confounding factors are so huge as to be almost laughable.
- There does seem to be some relationship between the gene and colon cancer, but ONLY in patients that had low folate intake and low folate blood levels. Moreover, there were a large number of confounding variables like smoking and diabetes that also increase the risk of colon cancer in the same group. No study could disassociate the various factors from MTHFR gene mutations.
I would bore you with a discussion of each paper, but as I reviewed each one, I could find none that associated one of the mutations with a particular condition that couldn’t be easily treated. The mutation itself didn’t cause the disease directly–it was the lack of treatment that lead to the disease.
Lynch is trying to tie the disease states to various MTHFR gene mutations – but, the mutation doesn’t cause the disease, but the lack of folate or excessive homocysteine, both of which can be treated quickly and successfully.
But the most glaring and horrific error in his list of “research” was a claim that thiomersal was associated with autism with those who have one of the MTHFR gene mutations. The evidence comes from whale.to, an antisemitic, hate-filled, chemtrail believing website run by a pig farmer. I kid you not.
Using whale.to as your evidence, which ranks at the bottom of the hierarchy of scientific evidence, is almost sufficient to dismiss everything that Mr Lynch claims with respect to MTHFR gene mutations, because if he couldn’t use real science there, it’s obvious that he really doesn’t understand science. But then again, Lynch is a woo-pushing naturopath, so there’s that.
The TL;DR version
- MTHFR gene mutations are a serious problem if left untreated.
- The consequences of MTHFR gene mutations can be easily diagnosed and treated, even in the young.
- MTHFR gene mutations are, as of the date of this article, unrelated to any vaccine adverse effect.
- MTHFR gene mutations do not lead directly to various disorders and diseases, only the the lack of a cheap and effective treatments do.
- Quacks who are pushing MTHFR gene mutations as the basis of a wide range of diseases are in it for money, because, it is easily and cheaply treated (in most cases).
Editor’s note: This article was originally published in May 2015. It has been extensively revised and updated to include more comprehensive information, to improve readability and to add current research.
- Reif DM, McKinney BA, Motsinger AA, Chanock SJ, Edwards KM, Rock MT, Moore JH, Crowe JE. Genetic basis for adverse events after smallpox vaccination. J Infect Dis. 2008 Jul 1;198(1):16-22. doi: 10.1086/588670. Erratum in: J Infect Dis. 2008 Sep 1;198(5):796. PubMed PMID: 18454680; PubMed Central PMCID: PMC2746083.