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MTHFR variant

Genetic tests · also printed as MTHFR, MTHFR C677T, MTHFR A1298C, MTHFR mutation, MTHFR genotype

Typical UK adult rangeExpected result: Not detected

Very common; the printed genotype is stored as text.

What this test measures

MTHFR variants are common inherited changes in an enzyme that handles folate. They are so common that most people carry at least one, and NHS testing is not recommended because the result does not change care.

Why doctors request it

Mostly seen on private panels; occasionally tested with homocysteine.

What commonly pushes it up

What commonly pushes it down

Everyday reasons for a value outside the range

About the sample

No fasting needed.

Written by a UK consultant physician. Typical UK adult reference ranges; your laboratory's own printed range takes precedence.

Got a report with MTHFR variant on it?

Upload a photo or PDF and see every line against the range your lab printed, explained in plain English. First report free.

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This is an educational summary of results you uploaded. It is not medical advice, a diagnosis or a treatment plan, and it does not replace the doctor who requested the test. If you are worried, or a result is marked outside range, discuss it with your doctor. Written and reviewed by a UK consultant physician. Reference ranges vary between laboratories.