I was wondering if anyone can make sense of my genetic testings. My GP is wonderful, amazing and I adore her - but even her knowledge in the area is slightly limited.

Here it is:

"Heterozygous for the DRB1*07-DQA1*02-DQB1*02 haplotype which is consistent with the DQ2 phenotype"

My blood tests are (although I had already been on the gluten free diet for 1.5 weeks at the time of the test):

Gliadin IgA Abs: 2 (Normal Range 0 - 20)
tTG IgA/IgG: 2 (Normal Range 0 - 20)

I understand that I have?? the DQ2 gene, but does this actually mean anything? The celiac blood test came back negative. Am I gluten sensitive? Is there any way to know?

My possible symptoms are migraine variant (prolonged aura 'derealization' without infraction), super super low magnesium, low iron (although I have never been a big meat eater) and low B12 .. generally vitamins are ok now due to supplements. Always very sleepy and tired.

Thanks so much.

My brain goes fuzzy when I start looking at all the numbers and letters of HLA types. HLA DQ2 and HLA DQ8 are definitely highly associated with celiac disease. About 30% of the population has one of these types, yet only 1% actually develop celiac disease.

Still, some believe that anyone with one of the main genetic types is predisposed to some level of gluten sensitivity and would benefit from a gluten free diet.

Beyond that... people with OTHER genetic types... can definitely have gluten sensitivity (although they rarely show villous atrophy on biopsy to indicate celiac disease). In the end, the genetic testing doesn't tell all that much.

Unfortunately they did not include the antigliadin IgG test, nor did they rule out IgA deficiency (total IgA). Some people don't make enough IgA (called IgA deficiency), and in this 10% of the population ... the IgA class of antibody tests become useless.

I question the resuls of the tTG IgA/IgG test because if they really ran both the IgA and IgG classes of this antibody... there should be two results? So, I'm not sure what was actually run. In someone with IgA deficiency, it is imperative tTG IgG is run.

Of all the tests, the antigliadin IgG test is the most sensitive for identifying gluten sensitivity (but that was not run on you). Since it is the least specific for "celiac disease" it is rarely used anymore. That is unfortunate...because it does indicate gluten sensitivity (an immunological reaction against gluten), and is the most meaningful of all for someone with a neurological presentation of gluten sensitivty (like migraine).

The bottom line for you based on these results is that it is unlikely you have celiac disease, but still not impossible because 1) they should have ruled out IgA deficiency or run all the IgG class antibody tests, and 2) up to 20% of biopsy proven celiacs can have negative blood tests especially with early less severe villous atrophy.

If you are symptomatic and have the predisposing genetic type, or have any family history of celiac disease... there is a small chance you could show villous atophy on a biopsy. Also... it is not uncommon for someone to have negative blood tests one year, but positive blood tests a few years later. If symptoms continue, you should be retested every couple of years, particularly since the predisposing genetics are there.

My personal thought is that you should definitely continue with a gluten free diet for at least six months to see if you notice any benefit. Remember it has to be very strict in order to get results; even small trace amounts of gluten could prevent you from improving.

You could also consider doing a stool test from Enterolab, which is the most sensitive test available, if you want a "second opinion". It is not a "mainstream" test, but it looks for the antibodies in the stool where they can be found long before they show up in the blood. I've known many people negative on traditional blood tests, and positive on stool tests, who go gluten free and never look back.

So... although your blood tests are far from a slam dunk for celiac disease... they also do not completely rule out the possibility of gluten sensitivity. The antigliadin IgG or stool test would be better for that, but in the end...a dietary trial may be the best test of all. Strict and for at least six months.

Antigliadin IgG has shown over and over to be the best available marker for extraintestinal manifestations of gluten sensitivity... which would include migraine related symptoms. (Antigliadin IgA and anti-tTG IgA are specific to gut damage.) You can have a neurological manifestation of gluten senstivity with or WITHOUT any evidence of gut damage. THere is a new antibody test, anti-TG6, which is being found in those with gluten related neurological symptoms... but it is not available yet... still being used only in research.

If you have any questions... please ask!

I wanted to add to the above some general explanation that:

Antigliadin antibodies show an abnormal immune system response to dietary gluten.

Anti-tTG (anti-TG2) antibodies show an abnormal immune system response targeting the intestinal villi. These are "autoantibodies" that directly attack the gut. This is what makes celiac disease an autoimmune disease.

Anti-TG6 are the new autoantibodies discovered associated with gluten ataxia and other neurological manifestations of gluten sensitivity, but they are not yet available commercially.

IgA class antibodies are more associated with gut manifestations of gluten sensitivity. IgG class antibodies are more associated with non-gut manifestations. This seems to hold true whether looking at antigliadin or anti-tTG antibodies.

So, the problem is the antibodies most relevant for celiac disease are least relevant when looking at a neurological manifestition of gluten sensitivity, and vice versa.

Most specific for celiac disease> anti-tTG IgA

Most specific for gluten related neurological disease> antigliadin IgG

This causes lots of problems when doctors are too focused on celiac disease and not the broader reaches of gluten sensitivity.