TMPRSS6: your iron tendency, straight up
TMPRSS6 leans you a little toward lower iron. But iron is one of the few nutrients you can actually take too much of, so the right first step is a blood test, not a supplement.
TMPRSS6 makes a protein that helps set your hepcidin level, and hepcidin is the switch that decides how much iron your gut absorbs. The G allele at rs855791 tends to come with slightly lower hemoglobin and slightly lower iron stores. It's a small, across-the-board nudge, not a deficiency on its own. So before you change anything, get the labs.
What TMPRSS6 does
If your ferritin and iron come back low, a gentle iron like bisglycinate is an easy fix. If they're fine, leave iron alone. It's one of a short list of nutrients where more is genuinely worse, not better.
One honest catch: if you also carry an HFE iron-overload variant, that warning beats this one every time. We would never point you toward iron when another of your variants is telling you to stay away from it. Pull up your HFE result too.
Your variants, decoded
The G allele tends to track with slightly lower iron and hemoglobin.
| AA | Typical iron and hemoglobin tendency. |
| AG | One copy of the G allele, so a slightly lower lean. |
| GG | Two copies of G, the lowest lean of the three, though your labs still have the final say. |
Genotypes are shown order-insensitively and on the forward strand; your own export may print the complementary letters — the meaning is the same.
What the research suggests
The G allele at your TMPRSS6 rs855791 (V736A) tends to come with slightly lower hemoglobin and iron stores. That's a modest, general lean, not a deficiency by itself. So check your ferritin and iron: if they're low, gentle iron helps; if they're not, skip it. Because iron is a nutrient you can overshoot, confirm with labs before you buy anything.
PubMed 39991164 · TMPRSS6 rs855791 & iron status / hepcidin
Educational only — not medical advice. “General evidence” means the finding is real but the supplement’s benefit isn’t unique to your genotype.
See this matched to your own DNA — free.
Upload your 23andMe or AncestryDNA file and get your actual TMPRSS6 result, plus every other actionable variant — each line cited, your file never stored.
Questions
Should I take iron with a TMPRSS6 variant?
Take iron only if blood work says you're actually low. The variant pushes your iron down a touch, but it's a small effect, and since iron is easy to overdo, the test comes before the supplement.