When we get into the realm of PCR/DNA testing for the gut, life gets a little confusing – and competitive! Recently both the Genova GI-Effects and the Diagnostic Solutions GI-MAP, the most popular tests of this type, have been updated. So, I took the chance to review them both again and come up with an answer to the question I get asked all the time:
Which gut test should I choose?
That’s a big question and you can always see my thoughts and comments on the Gut Tests Overview here. However, for today, let’s concentrate on the difference between the two PCR tests.
First, here is what has changed with both of them to keep you up to date.
The GI-MAP has quite simply added a load more markers – at no extra cost. Bonus. It includes viral pathogens, bacteria, worms, yeasts, parasites and comprehensive antibiotic resistant genes, alongside intestinal health and immune markers.
Now including 22 new markers:
- 5 additional H. pylori virulence factors (7 total)
- Epstein-Barr & Cytomegalovirus
- Phyla microbiota ratios
- 5 worm species
- Additional autoimmune bacterial triggers
- Protozoan parasites
All very useful!
The GI-Effects has not added any more markers but they have added a whole new reporting system that helps you see how the markers found might affect you clinically.
They are reporting on:
In other words, which markers are related to those conditions above and which do you have? I think that is practically very useful.
But there is no getting over the fact that GI-MAP includes far more markers for less money, so it depends what you want. Doesn’t it always? Sorry. Why can’t they just invent a GI-MAP that has good reporting like the GI-Effects one? That would be FAR too simple 😉
I’ve updated the Gut Tests Overview today for you, and here’s the bit on DNA testing:
Molecular DNA/PCR Testing
Here, you have a choice of two tests. Diagnostic Solutions’ new GI-MAP (Microbial Assay Plus) measures opportunistic organisms (including H pylori and its phenotypes, which is an add-on with the other tests usually and a very useful one to look at), normal flora, yeasts, parasites, viral pathogens, worms and antibiotic resistance genes as well as absorption markers (Elastase), inflammation (lactoferrin) and immunology (SIgA). It also includes occult blood and an anti-gliadin test. You can see a sample report and collection instructions here. Note that zonulin (a leaky gut marker) at the bottom of the sample report is an add-on, but I have listed a separate discounted GI-MAP with stool Zonulin for you to make life easier if you need that. To get the antibiotic resistant genes – for no extra cost – just tick the box on the requisition form in your kit.
And, if you want to read much more deeply about microbiome testing using PCR and see the whole list of pathogens included, see Diagnostic Solutions’ white paper here. You don’t get a lot of interp help or a pretty report on this one but they have written the huge white paper above which certainly will help you. This is returned to the UK lab for onward shipping.
You can also do PCR testing using the Genova GI Effects Comprehensive test. This measures similar, fewer pathogens as well as markers for absorption (elastase, fecal fat), inflammation (calprotectin, EPX etc) and immunology (SIgA). I like the fact it includes the SCFAs including the butyrate level as I see that a lot as a main cause of leaky gut (this is also in the DD CSAP tests which is one reason I like it). If you read the GI Effects Interpretation Guide, it shows how each bacteria is linked to illness. It can be very useful to make connections, of course, if a bacteria comes up which matches your symptoms – at least you have more of an idea what’s causing it! I do like their instant interpretation on the report and the Interpretive guide is very useful. Again, returned to the UK lab for onward shipping.
Overall: I would say that the GI Effects test is a very useful report if you are looking for a good general PCR/DNA test to check if any pathogens are causing illness and need a general screen of your gut with some info on what, in-vitro, is likely to kill it. The GI-MAP comes into its own if your main need is to check as many pathogens as possible; it simply includes a lot more, especially the H Pylori and the different types, the viruses, which antibiotics you may have a resistant gene for and a standard anti-gliadin gluten test (although I will never take a negative here as enough!). Check the sample reports and read up to establish which test covers what you most want to know.
OK, hope that helps. I’ll keep the Overview updated for you as things change, which they inevitably do, but I thought this might be useful for that ‘GI-MAP or GI-Effects test?‘ question when it crops up – a lot.