I’m reading the University of Chicago Celiac Disease Center’s free ebook Jump Start Your Gluten Free Diet: Living with Celiac/Coeliac Disease & Gluten Intolerance. As I read I find I’m a little frustrated. I wish someone had told me sooner that celiac disease was a genetic disease – that is, there is a gene mutation that makes you at increase risk of developing the disease at some point in your lifetime (HLA-DQ2 or HLA-DQ3). I get a little angry as to why not one of my health providers thought to tell me this – when I clearly indicate on my file (and mention regularly) that my father has celiac disease. But then I realize, his diagnosis was so long ago (20 or so years). They did not know then what they know now.
HLA tests for the class II heterodimers DQ2 and DQ8 are commercially available. Note that while the DQ2 or DQ8 genotype is considered necessary to develop CD, the presence of either one does not confirm the diagnosis. Conversely, the absence of both HLA types has a negative predictive value of over 99% and virtually excludes the diagnosis of CD. (ref here)
Very few health professionals actually know anything about celiac disease, and very few know that there is a simple genetic test to determine if you are predisposed to it. I found out that I had the genetic link only a few days after my dermatologist called to say “it looks like you might have a wheat allergy”. I had chosen to do the 23 and me genetic testing to see if there were any indicators (or counter-indicators) for me taking tamoxifen (relating to breast cancer treatment options). Since the tests take 5-6 weeks to return, I had almost forgotten about them. When the results did come back, one of the generic risk factors listed was for HLA-DQ2-Related, which indicated that I had the variant so I was at higher risk for developing celiac disease. Here is the thing, this is a simple spit in a tube, pay $200, and wait 6 week test. It is relatively inexpensive and not invasive. If you have a family member who has celiac disease, you should ask your doctor for this test (and if they say no, then 23 and me is an option!).
If someone is positive for the gene, then they should be tested regularly (yearly) for the anti-bodies. This is because celiac disease can develop at any stage in ones life – it doesn’t not necessarily present immediately.
The two key tests to run are the DGP-IgA and DGP-IgG. These antibodies are actually more promptly and fully responsive to a strict gluten-free diet, so their numbers should be as close to zero as possible, indicating a minimal antibody response to gluten. (page 25)
Again, these are simple blood tests. Minimally invasive. These are also the tests that someone who does have celiac do on a regular basis to ensure they are maintaining a gluten-free diet. The reason to test regularly is to help confirm that you are gluten-free – which isn’t always obvious. If you think you are, but you are not, then you need to examine your diet (and medications and supplements) to see where you are getting the hidden source of gluten. If you are positive for the gene, then this test can help determine if you have developed celiac disease (assuming you are eating gluten).
And so, with that, I am now telling all my close blood relatives. If you haven’t been tested for the celiac gene, you should ask your doctor for the test. You may not have celiac disease, but you may also have silent celiac (disease with no physical symptoms). Other illnesses and allergies may be celiac.
On a side note, I’m happy to report that with a gluten-free diet, I can eat a lot of things that I thought I was allergic to. I’m able to eat tomatoes again, and quinoa, and kale. I’m also tolerating lactose (not needing to take pills to eat most dairy). So many yummy foods that I had to cut out of my diet because I thought they were the cause of various symptoms (mostly blisters and eczema, which turned out to be dermatitis herpetiformis – the skin infestation of celiac disease – and why it was my dermatologist that made the initial diagnosis).