Genetic testing is available that can show whether you carry the genetic predisposition for developing gluten sensitivity or celiac disease. It is not diagnostic of active disease, but it may provide supportive information in cases where someone is symptomatic, but fails to meet the rigid criteria for a solid celiac diagnosis. It is also used to rule out Celiac Disease in those who do not carry the genetic predisposition for Celiac Disease.
95% of all those with celiac disease will show one of two genetic markers, HLA DQ2 (90%) or HLA DQ8 (5%). As many as thirty percent of the population carry this genetic makeup but only one percent develop Celiac Disease.
Another marker, HLA DQ1, has been identified by both Dr. Kenneth Fine and Dr. Marios Hadjivassilou as being associated with a Non-Celiac Gluten Sensitivity. While those who carry HLA DQ1 rarely show villous atrophy, it does happen on occasion. Since about 1-2% of biopsy proven celiacs carry the HLA DQ1 gene, it may be questionable practice to rule out Celiac Disease solely by the absence of the main genes (HLA DQ2 or HLA DQ8).
While HLA DQ1 is not recognized by most celiac experts as being associated with celiac disease, Dr. Hadjivassilou has found HLA DQ1 in about 20% of his gluten sensitive (antigliadin positive) neurological patients. The remaining 80% have either HLA DQ2 or HLA DQ8 consistent with the celiac population.
How can I be tested to see if I'm genetically predisposed?
Genetic testing may be done through blood sample or by a cheek swab. Your doctor could order the blood work for you, but there are also labs available where you may order the tests yourself.
Because Enterolab is the only lab I know of which also looks for the genetic types associated with a non-celiac gluten sensitivity (like HLA DQ1), I recommend this lab for genetic testing. This is important because~
From "Gluten sensitivitiy as a neurological Illness" by M Hadjivassiliou, R A Grunewald, G A B Davies-Jones:
"Within the group of patients with neurological disease and gluten sensitivity (defined by the presence of anti-gliadin antibodies) we have found a similar HLA association to that seen in patients with CD: 70% of patients have the HLA DQ2 (30% in the general population), 9% have the HLA DQ8, and the remainder have HLA DQ1. The finding of an additional HLA marker (DQ1) seen in the remaining 20% of our patients may represent an important difference between the genetic susceptibility of patients with neurological presentation to those with gastrointestinal presentation within the range of gluten sensitivity."
On HLA testing:
HLA-DQ2 and -DQ8 signatures of gluten T cell epitopes in celiac disease.
PMID: 16878175 Aug 2006
PMID: 16865785 July 2006