Interesting Info On Gene Testing

[chrissy]

my family has now been enrolled in the celiac study being done at the university of california, irvine. we should be getting the tests kits in the mail soon. i learned some really interesting info from the gal that is in charge of the study. she said it is possible for a child with diagnosed celiac to have neither of his parents show the celiac gene with testing. it has to do with the fact that there are 2 different subtypes of the DQ2 gene and if you don't have the right combo, you won't test positive for the gene. her example was that i could have 2 of the same subtype and my husband could have 2 of the other subtype, which would make neither of us test positive, but if we each passed on one of our subtypes so our child got a combo then our child would test positive for the gene. she said that they have had one family in the study that wanted to know what side the celiac came from----but they were not able to tell them. i am assuming that this is probably not something that is common. the study has been going on since 1996. they are trying to find a more specific marker for celiac disease since they know that there are more genes involved than DQ2 and DQ8. i have asked her for more info so i could understand this a little better. i'll let ya'll know if/when i get things a little more clarified.

[trents]

I wonder if anyone has done genetic studies on Celiac disease that would shed light on why the disease begins to express itself in infancy/early childhood with some people but not until adulthood with other people and why some show the classic GI symptoms and some, like me, have the "silent" form with little or no obvious GI distress?

Steve

[chrissy]

i just read something about that very thing yesterday. (age of the expression of celiac) the article said that in the USA, it is more often diagnosed in adults, but in another country (can't remember, sorry) it is more often diagnosed in childhood. it was first thought to have to do with the knowledge of our docs---but now they feel like there is another reason, but i don't think they had an answer for why. in one country there was alot of wheat in baby foods------when the wheat was lessened considerably, the rate of childhood diagnosis went down.

[Jennas-auntie]

Yes this is interesting. There have been multiple studies on this, here is one of the first that described this scenario (why the incidence rose or fell). Open Original Shared Link

They basically theorize that the genetics is remaining the same in the UK and Sweden, but that the delay of introduction of gluten to the diet and breastfeeding can lower the childhood incidence. These people may still develop celiac in adulthood, but they aren't getting so many early cases. However, overall gluten intake in Sweden almost doubled according to this study, I believe, so even though there was more breastfeeding + a delay in introduction of gluten, their cases in childhood were still high. The overall "dose" a child gets is also likely important.

As for why some people are "silent" and others are not, some people have more involvement than others, according to Dr. Greene. Since you have about 22 feet of small intestine, the more overall involvement you have the worse symptoms you can get. On the other hand, some people don't have a lot of symptoms but when you get in there for a biopsy it can look pretty obvious.

"Some people can be critically ill with severe malabsorption, and others can be completely well," says Peter Green, MD, director of the Celiac Disease Center at Columbia University. "So there's an enormous spectrum, and we don't know why one person can nearly die and another person is without symptoms."

I've read that people with "silent" celiac disease sometimes present with a first symptom of lymphoma. They know this because in Europe, they may test you for celiac if you come down with that. Unfortunately, it isn't a nice thing to have your first symptom be high grade intestinal lymphoma.

[ladyx]

Yes this is interesting. There have been multiple studies on this, here is one of the first that described this scenario (why the incidence rose or fell). Open Original Shared Link

They basically theorize that the genetics is remaining the same in the UK and Sweden, but that the delay of introduction of gluten to the diet and breastfeeding can lower the childhood incidence. These people may still develop celiac in adulthood, but they aren't getting so many early cases. However, overall gluten intake in Sweden almost doubled according to this study, I believe, so even though there was more breastfeeding + a delay in introduction of gluten, their cases in childhood were still high. The overall "dose" a child gets is also likely important.

As for why some people are "silent" and others are not, some people have more involvement than others, according to Dr. Greene. Since you have about 22 feet of small intestine, the more overall involvement you have the worse symptoms you can get. On the other hand, some people don't have a lot of symptoms but when you get in there for a biopsy it can look pretty obvious.

"Some people can be critically ill with severe malabsorption, and others can be completely well," says Peter Green, MD, director of the Celiac Disease Center at Columbia University. "So there's an enormous spectrum, and we don't know why one person can nearly die and another person is without symptoms."

I've read that people with "silent" celiac disease sometimes present with a first symptom of lymphoma. They know this because in Europe, they may test you for celiac if you come down with that. Unfortunately, it isn't a nice thing to have your first symptom be high grade intestinal lymphoma.

I read that gluten comes through breastmilk...My son had seizures everytime he breastfed when he was only 4 days old....he refused to eat for 8 hours and the seizures stopped but retured within 5 min of breastfeeding of course the doctors tried to convince me that it could not be anything in my milk...because I wasn't taking any meds...I think the reason that so many kids are not diagnosed is because peditricians are so ignorante about celiac diease...when I took my son to the pediatrican when he couldn't stop throwing up for weeks at time they did hundred of tests over almost a year and never once came close to diagnosing celiac diease even though I had told them that he broke out in a rash sometimes around his mouth when he ate a sandwich. They just gave up on diagnosing him all together and told me to take him to the Emergancy room. Crazy doctors that is all I have to say.

[mommida]

The ped gastro had asked us if we would participate in further genetic studies, we said yes. We have not been called for any further study. We are in the pattern. My daughter tested positive for both DQ2 and DQ8. My genetic test was negative, but my daughter and I both react the same for gluten ingestion. My symptoms were silent before my pregnancy for my daughter. My son has most of my silent symptoms and C, we have put him on a gluten free diet. His genetic test was negative, but his symptoms have cleared up. My husband has not been tested, yet. He feels testing is obviously useless, witnessing two family members that obviously have serious problems with gluten test negative.

We seem to have the unrecognized Celiac/gluten intolerant gene they are looking for.

L.