Search "DNA test" and you will find dozens of options that all promise to explain your genes. The harder problem is not finding a DNA test, it is knowing which one actually answers your question. A comprehensive panel, a methylation-specific test, a combined Gold Genetic test, and a single-marker test like MTHFR are built to do different jobs, and ordering the wrong one usually means paying twice.
This guide walks through the i-screen DNA and genetics range by the question you are actually asking, not by product name, so you can order the right test once.
Start with what you actually want to know
Before comparing products, work out which of these sounds most like you.
- "I want the broadest possible snapshot of my genetics." Start with the DNA Comprehensive Health Report.
- "I'm specifically interested in methylation, detoxification or MTHFR." Start with the Genetic Methylation Check, and read the note on MTHFR further down before you order.
- "I want both of the above, and I'm comfortable paying for the depth." The Gold Genetic Test combines a broad genetic panel with methylation-specific insight.
- "I have one specific question", such as a family history of iron overload, or a question about medication response. A targeted single-marker test usually answers it more directly, and for less, than a broad panel will.
- "I've already tested and want to know what my results mean." Skip to "Already tested?" further down.
Comparing i-screen's DNA tests at a glance
| Test | Sample | What it covers | Price | Best for | | --- | --- | --- | --- | --- | | DNA Comprehensive Health Report | Cheek swab | 92 genes and 113 SNPs across digestion, energy, hormones, stress and cognitive performance, methylation, inflammation, athletic performance, DNA protection & repair and detoxification | £225 | The broadest single genetic snapshot | | Genetic Methylation Check | Cheek swab | 8 core methylation and detox genes: both MTHFR variants, plus COMT, CBS, MTR, MTRR, MTHFD1, PEMT and AHCY | £225 | A specific focus on methylation and detox pathways | | Gold Genetic Test | Cheek swab | 50+ genes across cardiovascular health, metabolic efficiency, hormonal balance, neurological function and gut health, plus a methylation profile | £305 (reduced from £450) | Wanting both a broad panel and methylation insight without ordering twice | | MTHFR Check (cheek swab) / MTHFR Check (blood draw) | Cheek swab or venous blood | The two MTHFR variants only (C677T and A1298C) | £115 / £270 | A single, specific MTHFR question, see the note below | | Haemochromatosis Check | Blood | Screens the HFE gene for hereditary iron overload | £215 | Family history of iron overload | | Pharmacogenomics (PGx) DNA Test | Cheek swab | How your genes may relate to your response to medications, across areas including pain management, mental health and cardiovascular care | £166 | Discussing medication response with your healthcare provider | | Nutrigenomics Check | Cheek swab | 45 genes across fat burning and weight, power versus endurance, appetite and cravings, and stamina | £155 | Diet and fitness personalisation specifically |
The DNA Comprehensive Health Report, Genetic Methylation Check and Gold Genetic Test are processed through a NATA-accredited laboratory in Australia. None of the tests above require a GP referral.
The broad panels: Comprehensive DNA vs Gold Genetic
The DNA Comprehensive Health Report and the Genetic Methylation Check are both cheek-swab panels, but they are built around different questions. The Comprehensive report leans into digestion, energy, hormones, stress, cognitive performance and athletic performance, while the Genetic Methylation Check leans into methylation and detoxification specifically, across eight core genes including MTHFR, COMT and CBS.
If you are not sure which of those two angles matters more to you, the Gold Genetic Test removes the decision by combining a broader panel with a methylation profile in one order, at £305 against £225 for either the Comprehensive report or the Methylation check alone.
Methylation and MTHFR: what to know before you test
Methylation and MTHFR are two different things that often get talked about as one. Methylation is a broad biological process, involved in detoxification, energy production and cellular ageing, that the Genetic Methylation Check looks at across multiple genes. MTHFR is one specific gene within that picture, involved in folate metabolism, and it can also be tested on its own via the MTHFR Check (cheek swab or blood draw).
Here is the part worth knowing before you order a standalone MTHFR test specifically. NHS genomic medicine services in England advise that MTHFR polymorphisms "do not result in the classical MTHFR deficiency and are not causally linked with any other disorder," and that there is no evidence of clinical utility in testing for them outside of specific research settings [1]. Around 60-70% of people carry at least one of the two common MTHFR variants, and about 10% carry two, so on its own a positive result says little about your individual risk of anything [1]. Guidance for pregnancy is also clear: people who carry these variants are still advised to take the standard dose of folic acid, rather than switching to an alternative folate [1].
That is not a reason to avoid the test, it is a reason to be clear about what it can and cannot tell you. An MTHFR result shows you which variants you carry, as a starting point for a conversation with your practitioner, not a standalone answer or a basis for changing your care. If your interest is in whether your methylation pathway is actually functioning differently in practice, rather than only which variants you carry, the Homocysteine Check or the Methylation Pathways Check measure what is happening now rather than what your genes predict [2][3][4].
Have one specific question? A targeted test may be the better buy
Not every genetic question needs a full panel. If you are asking one specific thing, a single-marker test usually answers it more directly and for less money.
- A family history of iron overload points to the Haemochromatosis Check, which screens the HFE gene for hereditary iron overload.
- A question about how you might respond to certain medications points to the Pharmacogenomics (PGx) DNA Test, best discussed with your prescribing healthcare provider.
MTHFR and haemochromatosis markers are also included within the DNA Comprehensive Health Report, along with APOE, so if more than one of these questions applies to you, the broader panel may work out more cost-effective than ordering tests separately. A cardiovascular or cognitive question specifically tied to APOE genotype doesn't currently have a standalone i-screen test in the UK; the Comprehensive report is the way to access that marker here. Coeliac disease genetic typing (HLA DQ2/DQ8) also isn't part of the current UK range; the Coeliac Check offers a different, antibody-based route into a coeliac question instead.
Genetics and how you eat
If your question is specifically about diet, fitness and lifestyle rather than health risk broadly, the Nutrigenomics Check covers 45 genes across fat burning and weight, power versus endurance, appetite and cravings, and stamina, a narrower and less expensive option than a full comprehensive panel if this is your main interest.
Already tested? Here is where the real value is
If you have already done a genetic test with i-screen, or elsewhere, the DNA result itself is only half the picture. The variants you carry are fixed, so there is nothing to re-test, but how you act on them benefits from a second look.
- A DNA Nutrition Assessment, a written dietitian review of your existing Genetic Methylation Check, DNA Comprehensive Health Report or similar result, turning it into supplement and lifestyle guidance.
- A Methylation Pathways Check, if you have already tested for methylation and want to see whether your pathway is functioning differently in practice, rather than only which variants you carry.
A word on consumer DNA tests you may have already done
If you have done a direct-to-consumer test such as AncestryDNA or a similar ancestry-focused kit, it is not a substitute for the tests above. Those kits are built for ancestry and broad trait estimates, not for accredited health markers, and the specific genes and variants reported rarely line up with the ones covered here. If health insight is what you are after, the panels on this page are the ones built for that purpose.
This article is general information, not personal medical advice. It does not diagnose any condition. Always discuss your results with a qualified healthcare professional.
