Genetic Testing

[jcb101503]

My son was diagnosed with Celiac at 3 years ago at age 3 based on an endoscopy. He had severe villi damage.

My wife and I just learned about the genetic testing available for Celiac and had our other children tested. Also, my wife and I were tested as we were curious who was at risk as neither of us have suffered issues with gluten. We tested at Prometheus who tests for DQ2 and DQ8. We found that none of us had these genes.

Thus, I am now stumped as to how our son could have celiac. In researching this today, I came accross the posts about DQ1 and DQ3 also being tested. Since these are not technically celiac genes but do apparently lead to gluten sensitivity, can their presence also cause intestinal damage?

Thanks Mike

[ravenwoodglass]

There are some other genes associated with celiac than just the DQ2 or DQ8. I am firmly diagnosed and have a rarer (in the US) celiac associated gene, DQ9. It is quite possible to be celiac and not have either of the two most common genes.

You could try testing at someplace like Enterolab as they do test for the other related genes if you are interested in finding out which of the other genes you folks carry.

[nora-n]

Did that lab test for half genes, meaning the 0501 or 05* alpha chain of the DQ2 gene?

I notice that many labs have started to test the alpha chains.

You can contact the lab and ask what they tested, and someone here did contact the lab and they ahd actually tested and knew which of the DQ genes were present, but they did not report them until asked.

That is probably because most doctors would have gotten totally confused with what that means. (it is hard enough for them to grasp DQ2 and DQ8, let alone the other DQ types, or heaven forbid which aplha and beta chains)

There were at least two people whose tests were mistyped here,

one was a mother whose son had DQ8 and she did have a diagnosis from years ago, with strong positive blood tests, and she was just curious if the DQ8 came from her or from teh other side of the family.

The test was negative for celiac genes, and she contacted the lab, telling them it must be wrong, and they sent the sample to another lab, who found the DQ8.

It appears DQ8 is harder to find than DQ2.

She also tried Enterolab, who found DQ8 at the first attempt.

Enterolab tests for all DQ types (but only the beta chains)

On the other genes:

DQ3 is very very similar to DQ8. (DQ3 is 7, 8 and 9 and they vary by only one base)

About 20% of professor Hadjuvassiliou's gluten ataxia patients were found to be DQ1 and not the typical celiac genes.

About 6% of all celiacs have half genes.

About 1-2% have other genes than DQ2or 8 or the half genes.