What Is the MTHFR Gene Mutation?
The MTHFR gene mutation is a variation in the MTHFR gene. This gene normally tells your body how to make the MTHFR protein. You need this protein to process folate, which helps your body make DNA.
You have two copies of the MTHFR gene — one from your mother and one from your father. These genes tell your body how to make the MTHFR protein, which you need to produce folate, a B vitamin. Folate is required to break down homocysteine, an amino acid. If you have an MTHFR gene mutation, your body may not break down folate as well as it should. This leads to increased levels of homocysteine, which potentially could cause health problems.
There are a few common variants of the MTHFR gene.
MTHFR gene variants
Two common MTHFR gene mutations include:
- MTHFR C677T. At the 677 position of the gene, the DNA base cytosine (C) is replaced by thymine (T). It’s the most common variant — in fact, more Americans have at least one copy of it than those who don’t. It’s also more common in certain ethnic groups, such as among Hispanic people. In the U.S., up to 40% of white people and Hispanic people have this mutation.
- MTHFR A1298C. This variant happens at the 1298 position in the gene, where the expected DNA base adenine (A) is replaced by cytosine (C). About 7%-12% percent of North American, European, and Australian people have this mutation. It’s less common among Hispanic people and Asian people.
While there are other MTHFR gene mutations, they are incredibly rare.
MTHFR Gene Mutation Causes
There is no specific cause of MTHFR gene mutations. Everyone has two copies of the MTHFR gene. You inherit one from your mother or one from your father. If either of them has a copy of the gene mutation, you have a 50% chance of inheriting that.
MTHFR Gene Mutation Symptoms
Most people with an MTHFR gene mutation show no symptoms. Very rarely, symptoms may include:
- Eye problems
- Abnormal blood clotting
- Skeletal problems
- Learning difficulties
MTHFR gene mutation physical signs
There are usually no physical signs of this mutation.
Conditions associated with an MTHFR gene mutation
The biggest concern with an MTHFR gene mutation is that you may be more at risk of developing homocysteinemia. This is a condition where you can’t properly process homocysteine — an amino acid produced by your body. As a result, you develop high homocysteine levels. It can affect your eyes and joints, and may also raise your risk of heart disease or stroke.
Research also suggests that people with an MTHFR gene mutation may be more likely to develop:
- Neuropathy. People with this mutation who have diabetes seem more likely to develop neuropathy or nerve damage.
- Thrombophilia. This is a condition where you’re more likely to develop blood clots.
- Spina bifida. Women with an MTHFR gene mutation may have a harder time processing folate, which could raise their risk of having a baby with spina bifida or other neural tube complications.
- Sudden hearing loss
- High blood pressure
- Pregnancy loss
- Mood problems
- Cleft lip and palate. This is a birth defect where there’s a split in either your upper lip and/or the roof of your mouth.
MTHFR Gene Mutation Test
The MTHFR gene mutation test is a blood test that looks for the two most common gene mutations. It can be done alone or as part of a group of genetic tests.
MTHFR gene mutation test cost
The cost of the MTHFR gene mutation test varies with insurance. You can also purchase tests online for anywhere from $65 to $249, but these tests aren’t FDA-approved. If you do choose one, check the label or online description to make sure that the lab is “CLIA certified.” This means that the lab is at least regulated by the federal government.
MTHFR gene mutation test results
Your test results will let you know whether you are positive or negative for the MTHFR gene mutation. It will also tell you whether you have one or two of the gene variants.
If you have the mutation in only one of your genes, it should not affect your health. If you have two copies of the C677T gene mutation or one copy of both the C677T and A1298C variants, you may have increased homocysteine levels. Your doctor may want to test you to know for sure. If you have one or two copies of just the A1298C gene variant, that shouldn’t affect your homocysteine levels.
If your test is negative, you don’t have either of these two MTHFR gene mutations. If your doctor ordered the test because your homocysteine levels were high, it’s most likely due to another cause, such as age, medications, or an underlying condition such as thyroid or kidney disease.
Do I need to get the MTHFR gene mutation test?
Even though the test is widely available, most medical experts don’t recommend that you use it. Most people with MTHFR gene mutations don’t have any health issues. An easier and cheaper option is to do a blood test to check your homocysteine levels. If it’s high, your doctor can talk to you about steps to lower it.
MTHFR Gene Mutation Treatment
There’s no need to treat MTHFR gene mutation unless you have high homocysteine levels. The best way to lower those is to take folic acid. Good food sources include:
- Fruits and vegetables (especially leafy green vegetables)
- Fortified breads and cereals
- Lentils
- Chickpeas
- Most beans
Your doctor may also want you to take a folic acid supplement, as well as a supplement for some of the other B vitamins such as vitamin B6 and vitamin B12. Just keep in mind that this may not lower some of the risks associated with high homocysteine levels, such as increased risk of blood clots and heart disease.
Living With MTHFR Gene Mutation
Methylfolate supplements
You may have heard that methylfolate supplements are important for people with MTHFR gene mutations. One widely touted supplement is 5-methyltetrahydrofolic acid, or 5-MTHF. The theory is that people with these gene variants are less able to absorb folate, so taking methylfolate may be an effective option.
However, the CDC says this isn’t true. People with the MTHFR gene variants can absorb all sorts of folate including folic acid. In fact, research shows that people with this gene mutation still process this nutrient, although the amount is about 16% lower. If you take 400 micrograms of folic acid a day (the amount found in most multivitamins), you should be fine.
MTHFR gene mutation in pregnancy
You don’t need to worry about MTHFR gene mutations in pregnancy. In fact, screening for a gene variant isn’t even recommended by the American College of Obstetricians and Gynecologists (ACOG). While there have been studies to show that people with MTHFR gene variants are more likely to have babies with neural tube defects, most of those studies were done in countries where there isn’t routine folic acid fortification. In the U.S., most women get enough folic acid in their diet from fortified foods. It’s also recommended that pregnant women get 400 micrograms of folic acid each day. That is thought to be enough to reduce the risk of neural tube defects in pregnant women — including those with MTHFR gene mutations.
The CDC reassures that all people with an MTHFR gene variant can process folate, including folic acid. If you’re pregnant, it’s more important to get 400 micrograms of folic acid daily, rather than worry about whether or not you have an MTHFR gene mutation.
Takeaways
The MTHFR gene mutation is a variation in the MTHFR gene that impacts your body’s ability to absorb and process folate. You inherit two copies of the MTHFR gene, one from your mother and one from your father. If you have an MTHFR gene mutation, your body may not break down folate as well as it should. This may lead to elevated levels of homocysteine. While this was initially thought to cause health problems, new studies suggest that isn’t the case. You don’t need to be treated for an MTHFR gene mutation unless you develop high homocysteine levels. Most people with an MTHFR gene mutation have a normal life expectancy.
MTHFR Gene FAQs
What does it mean if you have the MTHFR gene?
Everyone has two copies of the MTHFR gene. Some people have an MTHFR gene mutation. It’s very common; in fact, more people in the U.S. have one or two copies of the most common variant — the MTHFR C677T variant — than those who don’t. You don’t have to get screened for gene variants, either. It should not have any impact on your health.
What are the symptoms of MTHFR deficiency?
Most people with MTHFR gene mutations don’t have any symptoms. Sometimes, it can cause higher levels of an amino acid called homocysteine. This can affect your eyes and joints, and may also raise your risk of heart disease or stroke.
What is the life expectancy of someone with MTHFR?
If you have a MTHFR gene mutation, you can expect to live as long as someone without it. MTHFR gene variants don’t appear to have an impact on life expectancy.
What foods should you avoid if you have MTHFR?
You may have heard that you should avoid foods high in folate if you have an MTHFR mutation. There’s no evidence to support that.
What does MTHFR feel like?
Most people with an MTHFR gene variation don’t even know they have it. It’s unlikely you would have physical symptoms.
Are eggs bad for MTHFR?
There’s no reason why someone with an MTHFR gene mutation would need to avoid eggs. Some animal studies even suggest that eggs may be protective against high homocysteine levels, but that’s preliminary. Groups such as the American Heart Association say it’s okay to eat the equivalent of an egg a day.
Why is MTHFR controversial?
MTHFR itself isn’t controversial; it’s a gene we all have. But there is some controversy surrounding MTHFR gene mutations. Groups such as the American College of Medical Genetics have issued guidelines recommending against testing for one of these gene mutations. While it was initially thought the mutations raised the risk of high homocysteine levels, heart disease, blood clots, and miscarriage, recent studies show no association. Many Americans have one of these variations and live full, healthy lives.
Is MTHFR passed from the mother or father?
You can inherit an MTHFR gene variation from either your mother or your father.
Can you fix MTHFR?
You cannot fix an MTHFR gene variation, and there is no need to “treat” one. Most people with an MTHFR gene variation don't develop health problems.