MTHFR Gene

What is the MTHFR gene?

MTHFR encodes methylenetetrahydrofolate reductase, a protein involved in one-carbon metabolism. It belongs to the Methylation category and is part of the Methylation & Neurotransmitters biological cluster. MTHFR encodes an enzyme that converts 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, the major circulating form of folate required for homocysteine remethylation.

Biological role and pathway

MTHFR is involved in the one-carbon metabolism pathway, which plays a central role in regulating physiological processes relevant to immune defence, cellular energy, and systemic homeostasis. Genes within the Methylation & Neurotransmitters cluster work together to maintain balanced function across interconnected biological systems.

Variants in genes within this pathway may influence an individual's predisposition to altered function in these systems — particularly under conditions of physiological stress such as viral infection or prolonged illness.

Known genetic variants

The following variants (SNPs) in the MTHFR gene have been studied in relation to methylation and chronic illness. Each variant represents a single nucleotide position where individuals may carry different alleles.

• rs1801133— MTHFR variant
• rs1801131— MTHFR variant

Conditions studied in relation to MTHFR

Research into MTHFR variants has explored associations with the following conditions. These are areas of scientific investigation and do not imply that MTHFR causes or treats any condition.

Genetic insights from DNA data

Consumer DNA files from 23andMe, AncestryDNA, and MyHeritage contain raw SNP data. When you upload your file to ChronicDNA, the analysis engine checks your genotype against a curated panel of 80+ genes selected for their relevance to Long COVID, ME/CFS, and connected biological pathways - some of which may include MTHFR and related genes in the methylation & neurotransmitters pathway.

The report is educational - it explains which variants you carry, what the research says about them, and how they fit into the biological pathways most relevant to chronic illness. Results are presented in plain English with appropriate scientific context, no medical jargon, no scare tactics. All results should be discussed with a qualified healthcare provider.

Related genes in the Methylation & Neurotransmitters pathway

MTHFR does not act in isolation. The following genes are functionally related and may be analysed together for a more complete picture of your genetic predispositions.

Frequently asked questions