How to Find Out if You Have an MTHFR Gene Variant

Genes Mentioned

• MTHFR

Of all the genes in the world of nutrigenomics, MTHFR is probably the best known. If you’re wondering whether you “have MTHFR,” you needn’t. Everyone has MTHFR genes, it’s just that some of us carry variants that reduce the function of the gene’s activity. Because variants in the MTHFR genes are quite common, many in the genetics world, such as 23andme, recommend against testing for mutations at all. While we agree that the “symptoms” blamed on changes in the MTHFR genes are wildly overstated in the functional health world, failing to test altogether is a mistake, especially for the Black community, where the clinically significant variants are far less common. If you are wondering whether you carry common mutations in the MTHFR genes, there are a number of tests that report on these genes.

DNA test kits that include MTHFR variants

Below are the top 4 DNA test kits that test for MTHFR variants:

1. Boston Heart Diagnostics
2. 23andme
3. Ancestry
4. Gene Food

MTHFR for 23andme users

If you have already purchased a 23andme test kit, you can login to see your MTHFR status by downloading your raw genetic data. If you have a 23andme account, you can login and see your MTHFR status in a few simple steps.

Step #1 – login and select “browse raw data”

23andme has made it much easier to navigate to your raw data file from the dashboard of a logged in account.

Step #2 – search MTHFR

Once you arrive at the raw data screen, you can search genes by name and see your call for the various SNPs they report on. There are many different MTHFR genes, although we will focus on a couple that are thought to be most clinically relevant. As you can see from the screen below, I typed in MTHFR directly into the 23andme search bar.

Step #3 – find the right version of the MTHFR gene

Once you arrive at the raw data search field for 23andme, you simply scroll down the page and find the relevant rsID of the MTHFR gene you’d like to evaluate. You will see numerous results with your status for each under the “Your Genotype” column. The most researched MTHFR variants are MTHFR C677T (rs1801133) and MTHFR A1298C (rs1801131). First, stop and notice how similar the rsID numbers are for these genes! Next, scroll the “Marker / SNP” column and find these variants. Minor allele for A1298C is – C or G. Minor allele for C677T is – T or A. If 23andme shows one copy of the minor allele that represents a “heterozygous” mutation. If two copies, that is a homozygous mutation. Here you can see Here, you can see my call for MTHFR C677T is G/G, meaning I do not carry a risk allele.

Other options

We have a blog post on our site detailing the various sites that process 23andme raw data. Although it doesn’t weigh heavily in our analysis, MTHFR is also one of the genes we report on in the methylation section of our custom nutrition plans.