AKA: The methylenetetrahydrofolate reductase gene / MTHFR gene
The MTHFR gene codes for an enzyme that is an important part of the methylation cycle.
What is the methylation cycle?
The MTHFR gene codes for an enzyme that is an important part of the methylation cycle. Methylation is the adding and removing of a methyl group (CH3) to amino acids, DNA, and other enzymes or proteins.
Methylation can turn on and off genes, maintain and repair your DNA, and alter proteins.
rs1801133
- G/G: typical
- A/G: one copy of MTHFR C677T allele (heterozygous), decreased by 40%
- A/A: two copies of MTHFR C677T (homozygous), decreased by 70 – 80%
rs1801131
- T/T: typical
- G/T: one copy of MTHFR A1298C (heterozygous), slightly decreased enzyme function
- G/G: two copies of MTHFR A1298C (homozygous), decreased enzyme by about 20%
MTHFR
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