An HFE gene test is a DNA test that checks for three specific variants — C282Y, H63D and S65C — in the gene that regulates how much iron your body absorbs. It's usually done on a blood or saliva sample.
It is not the same thing as an "iron blood test." Iron studies (ferritin and transferrin saturation) measure how much iron you currently have. The HFE test explains why. In practice, iron studies come first and genetic testing confirms.
The two tests people confuse
Search for "HFE blood test" and you'll get results for two completely different investigations. Both involve blood. They answer different questions, and mixing them up is the single most common source of confusion for people trying to sort out an iron problem.
| Iron studies | HFE genetic test | |
|---|---|---|
| Measures | Iron in your blood right now | Your inherited DNA sequence |
| Key numbers | Transferrin saturation, ferritin | C282Y / H63D / S65C genotype |
| Changes over time? | Yes — daily, with diet, inflammation, illness | Never. One result is permanent |
| Repeat testing | Routine, often annually | Once, unless reliability is in question |
| Answers | "Do I have too much iron?" | "Is this genetic, and will it recur?" |
You need both to reach a diagnosis. A high ferritin with no genetic explanation is a different clinical problem than a high ferritin in a C282Y homozygote, and they're managed differently.
The order clinicians actually use
Guideline bodies are consistent on sequence: measure iron first, genotype second. The reasoning is that HFE variants are common and mostly harmless, while iron overload is the thing that actually damages organs. Testing genotype in someone with normal iron studies produces a lot of anxiety and very little information.
Step 1 — fasting transferrin saturation and serum ferritin. Transferrin saturation is the more specific marker; ferritin rises with inflammation, infection, liver disease and alcohol, so it produces false alarms on its own. Transferrin saturation normally sits between 15% and 30%.
Step 2 — genotype if the numbers are abnormal. HFE genetic testing is recommended when transferrin saturation is 45% or above. Notably, elevated ferritin alone, without raised transferrin saturation, is generally not considered a sufficient trigger — that pattern more often points to metabolic or inflammatory causes.
European guidance sets sex-specific thresholds for provisional iron overload: transferrin saturation above 45% with ferritin above 200 µg/L in women, and above 50% with ferritin above 300 µg/L in men and postmenopausal women.
Fast before the blood draw. Transferrin saturation rises after eating, so a non-fasting sample can push a normal person over the 45% line. If a first reading is high, standard practice is to repeat it fasting before doing anything else. Booking the fasting test up front saves a round trip.
The exception: if a first-degree relative has confirmed HFE hemochromatosis, genetic testing is appropriate regardless of your iron numbers. A documented family history in a first-degree relative is an independent indication, because you're identifying risk before iron has had time to accumulate — which is the entire point.
What the test checks for
A standard targeted HFE panel genotypes three positions:
- C282Y (
c.845G>A, rs1800562) — the clinically important one. Disrupts the HFE protein's ability to reach the cell surface, which lowers hepcidin and lets iron absorption run unchecked. - H63D (
c.187C>G, rs1799945) — much more common in the population, much weaker in effect. Rarely causes iron overload without a second hit. - S65C — uncommon, mild, and not included by every laboratory.
The lab reports which variants you carry and on how many copies. That's it — three data points that don't change for the rest of your life.
Reading your result, genotype by genotype
| Genotype | What it means | Typical action |
|---|---|---|
| C282Y / C282Y (homozygous) | The classic hemochromatosis genotype. Accounts for the large majority of cases in European-ancestry populations | Ongoing iron monitoring; phlebotomy if iron is loading. Test first-degree relatives |
| C282Y / H63D (compound heterozygous) | Modestly raised risk. Iron overload is unusual in this genotype and usually needs a cofactor such as alcohol or fatty liver | Monitor iron; investigate other causes if ferritin is high |
| C282Y / normal (carrier) | Carrier. Not expected to cause iron overload on its own | Relevant for family planning; look elsewhere for a raised ferritin |
| H63D / H63D | Common. Occasionally associated with mildly raised iron markers, rarely with organ damage | Reassurance plus routine follow-up if markers are abnormal |
| H63D / normal | Very common. Considered clinically unremarkable | No specific action |
| No variants | HFE hemochromatosis effectively excluded | If iron is genuinely high, investigate non-HFE causes |
A positive genotype is not a diagnosis. Diagnosis in C282Y homozygotes requires the genotype plus biochemical evidence of iron overload; for other genotypes with high iron markers, confirming hepatic iron overload on MRI or biopsy is usually needed. Plenty of homozygotes never load iron at all — a point we cover in our guide to how hemochromatosis is inherited.
Sequence once, answer every future question
A targeted HFE panel reads three positions. Whole genome sequencing reads all of them — HFE, plus SLC40A1, HJV, HAMP and TFR2, plus everything you haven't thought to ask about yet. Dante Labs delivers your raw data, so the file is still useful in ten years.
Compare Dante Labs WGS → Code GENOME — 10% offAffiliate link. Consumer sequencing is not a clinical diagnostic — confirm findings through your doctor.
Who should get tested
Testing is clearly indicated if you have:
- Unexplained transferrin saturation of 45% or higher, ideally confirmed on a fasting sample.
- A first-degree relative — parent, sibling or child — with confirmed HFE hemochromatosis. Siblings of a homozygous person have a 1-in-4 chance of the same genotype.
- Unexplained liver disease with raised iron markers, even where another liver diagnosis already exists.
- Symptoms that fit the pattern alongside abnormal iron studies — persistent fatigue, joint pain especially in the second and third knuckles, unexplained diabetes, or abnormal liver enzymes.
Testing is generally not indicated for people with normal iron studies and no family history. Guidance is explicit that HFE testing is not recommended for general screening in that situation — a position that reflects the low penetrance of these variants and the cost of investigating findings that never become disease.
That said, the guideline position and the personal-genomics position genuinely differ. If you're sequencing your genome anyway, HFE comes along for free, and knowing early is exactly what prevents the outcomes worth preventing. What guidelines discourage is spending healthcare money on it, not the knowledge itself.
How to get one
Through your doctor. The standard route. Ask for iron studies first; if transferrin saturation comes back at 45% or above, HFE genotyping is the logical follow-up and is generally covered by insurance or national health systems when that criterion is met. Some plans require documented pre- and post-test genetic counselling.
Direct-to-consumer targeted testing. Several labs sell standalone HFE panels without a doctor's order. Fast and inexpensive, but you get three data points and no clinical context — and a result you don't know how to act on is of limited use.
Whole genome sequencing. More expensive up front, but it reads HFE along with every other gene, including the non-HFE iron genes a targeted panel ignores. If you're weighing the options, our comparison of whole genome sequencing and genotyping arrays covers what each technology can and can't see, and our Dante Labs vs Sequencing.com comparison looks at the two main consumer providers.
A note on 23andMe-style arrays. Genotyping chips typically do include the C282Y and H63D positions, so many people first learn their HFE status that way. Array results are a reasonable prompt to speak to a doctor, but they are not clinical-grade, and a finding that would change your medical care should be confirmed by a clinical laboratory.
What an HFE panel misses
Three real blind spots are worth knowing about before you treat a negative result as the end of the matter.
1. Rare HFE variants. A targeted panel checks three positions. More than twenty other pathogenic HFE variants have been described. Full HFE sequencing may be necessary for people without northern European ancestry, where the common variants are rare but iron overload still occurs.
2. Non-HFE iron genes. Ferroportin disease (SLC40A1) is the second most common inherited iron overload condition and is inherited dominantly. It's invisible to an HFE panel. So are the juvenile forms caused by HJV and HAMP, and type 3 caused by TFR2.
3. Everything that isn't genetic. Most high ferritin results are not hemochromatosis. Metabolic syndrome, non-alcoholic fatty liver disease, heavy alcohol use, chronic inflammation, and repeated transfusions all raise iron markers. A clean HFE result doesn't mean your ferritin is fine — it means the explanation is elsewhere.
Iron is one gene family among thousands
If you're already testing for a specific reason, sequencing the whole genome costs little more than testing one gene well — and covers pharmacogenomics, carrier status and other actionable findings in the same run.
See what whole genome sequencing covers → Code GENOME — 10% offAffiliate link. Educational content — not a substitute for clinical genetic testing.
Common questions
What is an HFE gene test?
It's a DNA test that looks for specific variants — most importantly C282Y, plus H63D and sometimes S65C — in the HFE gene on chromosome 6. HFE helps regulate hepcidin, the hormone controlling how much iron your intestine absorbs. The test is normally performed on blood or saliva and, because your DNA doesn't change, only needs doing once.
Is an HFE blood test the same as an iron test?
No. Iron studies measure transferrin saturation and ferritin — how much iron is in your body right now, which fluctuates. The HFE genetic test reads your inherited DNA and never changes. Both may be drawn from blood, which is why the names get conflated, but they answer different questions and are usually done in sequence rather than together.
Do I need a doctor's order for an HFE test?
Not necessarily — direct-to-consumer HFE panels and whole genome sequencing services are both available without a referral. But results that would change your medical management should be confirmed through a clinical laboratory, and going through a doctor means iron studies get done alongside, which is what determines whether the genotype matters.
What transferrin saturation triggers genetic testing?
The widely used threshold is 45% or above, ideally on a fasting sample and preferably confirmed on a repeat. European guidance uses sex-specific combinations: above 45% with ferritin over 200 µg/L in women, and above 50% with ferritin over 300 µg/L in men and postmenopausal women. Raised ferritin without raised transferrin saturation is generally not on its own an indication for HFE genotyping.
Does the HFE test check for all types of hemochromatosis?
No. A standard panel covers HFE-related type 1 only. Type 4 (ferroportin disease, SLC40A1), the juvenile types 2A and 2B (HJV, HAMP) and type 3 (TFR2) are all missed. If iron overload is clearly present but HFE comes back negative, broader sequencing is the logical next step.
How much does an HFE gene test cost?
Prices vary widely by country, laboratory and whether you meet coverage criteria. When ordered by a doctor for someone with a transferrin saturation of 45% or higher, or with an affected first-degree relative, it is often covered by insurance or a national health system. Direct-to-consumer targeted panels are typically inexpensive; whole genome sequencing costs substantially more but covers far more ground. Check current pricing directly with the provider, as it changes frequently.
Sources
- College of American Pathologists, Genetic Haemochromatosis clinician handout
- College of American Pathologists, Hereditary Hemochromatosis for Clinicians
- EASL Clinical Practice Guidelines on haemochromatosis
- Lab Management Guidelines: HFE Hemochromatosis Genetic Testing, V2.0.2024
- Lab Management Guidelines: HFE Hemochromatosis Genetic Testing, V1.0.2026
- Hemochromatosis mutations, dementia and brain iron deposition (genotype risk data)
Medical disclaimer. GenomeTesting.org publishes educational content about genetics and consumer genomic testing. Nothing here is medical advice, a diagnosis, or a substitute for care from a qualified clinician or genetic counsellor. Decisions about testing, treatment, or interpreting your own results should be made with a healthcare professional who can see your full history.
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