MTHFR, DNA Analysis
A one-time genetic test for variants in the MTHFR enzyme, which converts folate into its active methylated form.
Explains stubbornly elevated homocysteine and guides which form of folate to supplement. Roughly 30–40% of people carry at least one variant, so this is common rather than exotic.
The plan of attack
In this order. Most people start at step four, which is why they change five things at once and learn nothing.
- Confirm the number is real
Nothing physiological affects this result. Your genotype is fixed. No fasting state, illness, supplement or medication changes it, and a repeat returns the same answer — worth saying plainly rather than leaving this section blank. Test once and never repeat it. Spend the money on the functional marker instead. - Read it with its partner
The practical value is in what it tells you to supplement. MTHFR status is widely over-interpreted online — it's a useful data point, not an explanation for everything. Draw it alongside: Homocysteine, Folate, Serum, Vitamin B12. - Work out which direction is yours
If it's high — Homozygous C677T reduces enzyme efficiency substantially and is associated with higher homocysteine.
If it's low — Normal function. - Fix it in this order
Nutrition. Leafy greens and legumes for natural folate. Some carriers do better avoiding synthetic folic acid in fortified foods and supplements in favor of methylfolate.
Lifestyle. Avoid smoking and excess alcohol, both of which further burden methylation.
Supplements. Methylfolate (5-MTHF) instead of folic acid, plus methylcobalamin B12 and P5P (B6). Add riboflavin — it's the cofactor for MTHFR and specifically helps C677T carriers. TMG/betaine provides an alternate methylation route.
Hormones. No hormonal intervention. Relevant preconception — discuss folate dosing with a provider.
Compounds. No peptide interaction.
Work down the list, not across it. Adding a compound on top of an unfixed diet is why generic protocols fail. - Retest
Never — fixed for life. Change one thing at a time, or the retest can't tell you which thing worked.
How to fix it
📚 Frosst P et al., Nat Genet 1995 — MTHFR C677T. Homocysteine Studies Collaboration, JAMA 2002.
🩸 Test your MTHFR, DNA Analysis
Order directly through Marek Diagnostics — no doctor's visit needed, drawn at any Quest location in the US. Code CAMERON applies 10% off automatically.
Order this test — 10% off → Browse all 102 markers →What MTHFR, DNA Analysis is usually tested alongside
On its own, one marker is a data point. These panels include MTHFR, DNA Analysis plus the markers that make it interpretable — each names every test, why it is on the list, and loads the whole set into your cart in one click at 10% off.
includes this + 4 more markers — You want the handful of genetic results that actually change what you do — tested once, never repeated.
What moves your MTHFR, DNA Analysis
1 supplement in the Vault have a documented effect on this marker, or are a reason to have measured it first:
Browse all 237 compounds & 350 supplements →
Would you feel it? Symptoms MTHFR, DNA Analysis helps explain
People rarely search for a marker — they search for how they feel. These are the complaints where this marker is worth checking, and whether it is a first-line test or a follow-up once the obvious causes are ruled out.
Why your MTHFR, DNA Analysis might be wrong
Most abnormal results are interference, not disease. These are the things that measurably move this specific marker — check them before you change anything. Each one says whether the number is wrong and should be repeated, badly timed and should be redrawn, or real with a cause worth explaining.
Your genotype is fixed. No fasting state, illness, supplement or medication changes it, and a repeat returns the same answer — worth saying plainly rather than leaving this section blank.
Test once and never repeat it. Spend the money on the functional marker instead.
MTHFR variants are extremely common — roughly a quarter of some populations carry two copies of C677T. Carrying a variant is close to unremarkable, and large studies have not shown the sweeping consequences attributed to it online.
Homocysteine is the functional test that actually matters. A normal homocysteine with an MTHFR variant means the pathway is working. Treat the number, not the genotype.
Different tests cover different variants. A report saying 'MTHFR negative' may simply not have assayed the variant you carry.
Check which variants were actually tested.
What MTHFR, DNA Analysis means in combination
A single marker tells you a little. Combinations tell you the story — these are the named patterns this marker takes part in, and what each one points at.
The pathway is working. MTHFR variants are extremely common — around a quarter of some populations carry two copies — and carrying one is close to unremarkable. Homocysteine is the functional readout, and a normal one says the genotype is not causing you a problem.
Treat the number, not the genotype. If homocysteine is raised, correct B12 and folate — with B12 first, always, because folate can normalise the anaemia while nerve damage continues.
What to test next
Markers rarely answer alone. These are the ones that put MTHFR, DNA Analysis in context — each with its own full breakdown.
Frequently asked questions
Result: normal, heterozygous, or homozygous for C677T and/or A1298C Ranges vary by laboratory and assay — always compare to the range printed on your own report.
No variants. Carrying a variant is common and manageable — not a diagnosis.
Homozygous C677T reduces enzyme efficiency substantially and is associated with higher homocysteine.
Normal function.
You can order MTHFR, DNA Analysis directly through Marek Diagnostics without a doctor's visit — drawn at any Quest Diagnostics location in the US. Code CAMERON applies 10% off automatically.