Tested negative to DQ2 and DQ8 genes but positive to DPG IGG

[kiriaussie]

Hi, I am new to the site. 

I have had ongoing gut issues for 2+ years now and last year began to suspect Celiac. 

I have migraines, fatigue (also had a ME/Chronic Fatigue Syndrome diagnosis as a child), dizziness, joint paint, chronic acid reflux, bloating, abdominal cramps. I went mostly off gluten for a couple of months and seemed to notice a difference in my symptoms, I also seemed to have a stronger reaction when I did have gluten after cutting it out. 
 

Decided to check my genes at the end of last year and the results came back negative. Everything I read says negative gene test = no celiac. However something in me felt like I should get the blood work to rule it out completely. I started a gluten challenge and I got Imaware's at home full Celiac panel, sent it in and got the results yesterday. I was shocked (expected negative results after the gene test) to see I came up positive for DPG IGG (other three antibodies were normal). I have had a read on the site and seen some people talking about how we may not yet know all of the celiac genes yet and that some people have been biopsy confirmed celiac without the two main celiac genes.

I guess my question is, could there be an alternative explanation for my positive DPG IGG? I have heard false positives are extremely rare and that false negatives are more common. Just trying to make sense of these seemingly conflicting results!

How common is it to be celiac without the main celiac genes? 

I should mention I am planning on seeing a Dr (hopefully a good GI) once I get back to Australia in the upcoming months (I have been living in the USA and until recently did not have insurance). I am hoping they will be able to do a biopsy and give more answers. I would really prefer to have a clear diagnosis before going off gluten again.

Thanks in advance for any insight that can be offered!

[trents]

kiriaussie, welcome to the forum!

Do you have a total IGA score from the serum antibody testing? Low total IGA can cause false negatives in the IGA antibody spectrum of testing. In that scenario, the IGG-IGA and the IgG can catch celiac disease. https://celiac.org/about-celiac-disease/screening-and-diagnosis/screening/ : "IgA deficiency in a patient may be indicative of other diseases that may cause villus atrophy, such as giardiasis, small-bowel bacterial overgrowth (SIBO) or common variable immunodeficiency (CVID)"

It is not unheard of to have celiac disease without have the two so far identified genes. This is likely why celiac genetic research is ongoing. Researchers (in Israel, I believe) are looking at a third gene that may be connected with celiac disease.

An endoscopy with biopsy will likely bring some clarity to the picture.

[kiriaussie]

Hi, thanks for your reply!

Unfortunately the test doesn’t seem to include my total IGA score, however I noticed something interesting about my results after checking them again.
 

My numbers for TTG IGA, TTG IGG and DPG IGA, all came up right at the beginning of the reportable range. Which seems strange. E.g. if the reportable range starts at 1.7 my number was 1.7.  I am curious to get my total IGA checked to see if that could be affecting my results.

 

 

[trents]

Do you have online access to the whole report in your patient portal?

[kiriaussie]

I believe so, I have all my numbers? And it shows all the results. I have a pdf it gave me to take to my Dr. I couldn’t see anything about my total IGA.

[frieze]

DQ9 is recognized in Europe.

[trents]

34 minutes ago, frieze said:

DQ9 is recognized in Europe.

Yes. I researched DQ9 and it appears to have some association with celiac disease. I just think there is a lot we don't know about the genetics of celiac disease and even less about the genetics of NCGS. And then there is the whole unfolding science of epigenetics. Epigenetics deals with DNA structures that allow for genetically driven changes in response to environment that do not involve mutations, i.e, a range of adaptability to external stimuli that is baked into the DNA. At least that's my understanding of it.

Edited February 14, 2022 by trents