MTR rs1805087 (A2756G): Health Outcomes and Methylation

This article is part of the PlexusDx Education Hub — your resource for evidence-based guidance on methylation & mthfr. Browse all Methylation & MTHFR education

The rs1805087 variant — also written as A2756G — sits in the MTR gene, one of the central genes in your body’s methylation machinery. If your genetic report flags this variant, it is worth understanding what MTR does, how the A2756G change affects it, and what research has linked to it. This is educational context about a pathway, not a diagnosis.

What the MTR gene does

MTR provides the instructions for methionine synthase, an enzyme at the heart of one-carbon metabolism. Its job is to convert homocysteine back into methionine, and it needs vitamin B12 as a cofactor and a methyl group donated by 5-methyltetrahydrofolate (the active form of folate). That reaction does two important things at once: it recycles homocysteine, and it helps regenerate the methyl groups the body uses for countless downstream processes, from DNA regulation to neurotransmitter balance.

The rs1805087 (A2756G) variant

rs1805087 is a single-nucleotide change in MTR where an adenine (A) is replaced by a guanine (G) at position 2756. At the protein level this produces a change from aspartate to glycine (often noted as D919G) near a functional region of methionine synthase. The G allele is relatively common in many populations. Research has examined whether it subtly alters enzyme activity and, in turn, how efficiently homocysteine is remethylated.

What the research shows

Studies of rs1805087 have most consistently examined its relationship with homocysteine levels, which reflect how smoothly the remethylation pathway is running. Elevated homocysteine is a marker researchers watch because it can signal that the recycling reaction is not keeping pace. Some studies report modest associations between the G allele and homocysteine or B12 status, and these signals often depend on how much folate and B12 a person is getting. The variant has also been studied in relation to cardiovascular traits, cognitive outcomes, and neural tube defect risk in offspring. These are population-level associations that frequently interact with nutrition — they describe tendencies, not certainties, for any one person, and effect sizes are generally small on their own.

How MTR connects to the methylation pathway

MTR does not work alone. It sits alongside MTHFR, which produces the 5-methyltetrahydrofolate that MTR uses, and MTRR, which helps keep methionine synthase active by regenerating its B12 cofactor. Together these genes form the remethylation arm of the methylation cycle. A variant in one gene is best understood in the context of the others, because the pathway’s overall efficiency depends on how the whole system — and your B12 and folate status — works together.

What your genetic insights reveal

Seeing an MTR result in context is more useful than seeing it in isolation. The Precision Peptide Genetic Test analyzes 14 pathways, 49 peptides, 150+ genetic insights, placing rs1805087 alongside related methylation-pathway variants so you can understand your one-carbon metabolism as a system. It is an educational map of predispositions, not a diagnosis — it tells you about your biology, not what to put in your body. Genetics is a guide, not a guarantee, and your results are best discussed with a qualified provider.

Frequently Asked Questions

What does the MTR rs1805087 variant do?

rs1805087 (A2756G) is a variant in the MTR gene, which encodes methionine synthase. This enzyme converts homocysteine back into methionine using vitamin B12 and active folate. The variant has been studied for subtle effects on enzyme activity and on how efficiently the remethylation pathway recycles homocysteine, often interacting with B12 and folate status.

Is the G allele of rs1805087 bad?

No — a genotype is a map, not a verdict. The G allele is common in many populations, and research shows only modest, nutrition-dependent associations with homocysteine and B12 status. Carrying it does not mean you have or will develop any condition. It is context for understanding your methylation pathway, best reviewed with a provider.

How does MTR relate to MTHFR?

MTR and MTHFR work in the same methylation cycle. MTHFR produces 5-methyltetrahydrofolate, the active folate that MTR’s enzyme uses to convert homocysteine into methionine. A third gene, MTRR, keeps the enzyme active. Because they function together, MTR variants are best interpreted alongside MTHFR and your folate and B12 status.

Can the Precision Peptide Genetic Test diagnose a methylation disorder?

No. The Precision Peptide Genetic Test is educational and maps genetic predispositions across pathways — it does not diagnose, treat, or prevent any condition. It reports variants such as MTR rs1805087 in the context of the methylation pathway so you can understand your biology and discuss it with a qualified healthcare provider.

Understand your methylation pathway in full: the Precision Peptide Genetic Test maps rs1805087 alongside related variants across your one-carbon metabolism — educational insight to review with your provider.

This article is part of the PlexusDx Education Hub. Browse all Methylation & MTHFR education

Disclaimer: The Precision Peptide Genetic Test analyzes how your genes influence peptide-related biological pathways. It does not recommend, prescribe, or determine which peptides you should use. Consult a qualified healthcare provider before beginning any peptide protocol.