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  • Writer's pictureJenny Ingles, CFCP

Genetics and Fertility

In recent years the MTHFR (pardon my language) gene mutation has gotten a lot of notoriety in the fertility world. It turns out that women with specific types of this mutation can suffer from infertility and/or recurrent miscarriage. But what is this gene and how can it affect fertility?

Before I dive into this, here's a little primer on genetics. Most of the time, when people refer to gene mutations or variants, they are talking about single nucleotide polymorphisms or SNPs (pronounced "snips") for short. If you are familiar with the double helix, you will note that it looks like a twisted ladder with rungs up and down it. Each "rung" on the DNA ladder is made up of a pair of chemical bases bonded together. An SNP is one of those chemical bases. To put it into perspective, an SNP is half of a "rung" on a DNA ladder. Each person's genome has roughly 4 to 5 million SNPs and most SNPs have absolutely no effect on a person's life. There are a few, however, that can have a huge impact. MTHFR and COMT are two SNPs that affect methylation and can cause fertility issues.

Methylation is a normal process in the body that tells genes how to behave. MTHFR is well known for disrupting the body from turning folate (an important B vitamin) into the usable form 5-methyltetrahydrofolate. So people with certain types of this mutation need to take methylated folate in order to use it properly. These people are also sometimes advised to avoid foods enriched with folic acid (synthetic folate) because recent research shows that folic acid can actually block the uptake of 5-methyltetrahydrofolate. Why does this matter in fertility? First, folate is essential in the proper growth of unborn babies, and deficiencies in it are known to cause neural tube defects. Second, certain MTHFR SNPs can cause sperm quality issues in men while others can affect egg quality in women.

COMT isn't as infamous as MTHFR (maybe because it doesn't look like a cuss word you would hear at a biker bar?), but it is very important in fertility. Specifically, COMT mutations can affect how the body processes and clears estrogen. It is suspected that COMT is linked with PCOS and possibly endometriosis. And because it can affect estrogen, it can cause defects in progesterone production. All of these things are bad news for women regardless of if they are trying to conceive or not.

What does it mean if you have one of these variants? Are you consigned to a life of ill health? Certainly not! First, how these affect you depends on which SNP you have. There are 3 common MTHFR SNPs and they all behave differently. There are 2 major COMT SNPs and they also are different. Second, how they affect you depends on if they are homozygous (double mutation) or heterozygous (single mutations). Some of these mutations are only important if you have a homozygous mutation. Third, you have control over how these mutations affect you.

The emerging and fascinating field of epigenetics shows us that even if we are dealt a less than stellar genetic hand in life, we can still win the game using a good strategy. Epigenetics is how your environment affects the way your genes behave. A perfect example is the one highlighted above where supplementing 5-methyltetrahydrofolate and avoiding folic acid can counteract certain MTHFR mutations. Diet, exercise, exposure to environmental toxins, stress, medications, supplements, and even other SNPs all play a role in how your mutation affects you.

Because I'm not a doctor (especially not your doctor), I cannot give you advice on how to manage your gene mutation. But I can give you hope. Many NaPRO doctors are recognizing the importance of gene mutations and many functional medicine doctors have been ahead of the curve on this for years. Charting with CrMS can also help your doctor determine which tests to run and also how your body is coping with (or not) your mutation. Contact one of our practitioners to get started today.

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