Celiac-Associated HLA-DQ Alpha 1 and DQ Beta 1 Medium-High Resolution DNA Typing, Blood
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Celiac disease (gluten-sensitive enteropathy) is mediated by T lymphocytes in patients with genetic susceptibility. This genetic association is with certain HLA genes in the class II region (DQ alpha 1, DQ beta 1).
For your convenience, we recommend utilizing cascade testing for celiac disease. Cascade testing ensures that testing proceeds in an algorithmic fashion. The following cascades are available; select the appropriate 1 for your specific patient situation. Algorithms for the cascade tests are available in Special Instructions.
-CDCOM/89201 Celiac Disease Comprehensive Cascade: complete testing including HLA DQ typing and serology
-CDSP/89199 Celiac Disease Serology Cascade: complete testing excluding HLA DQ
-CDGF/89200 Celiac Disease Comprehensive Cascade for Patients on a Gluten-Free Diet: for patients already adhering to a gluten-free diet
To order individual tests, see Celiac Disease Diagnostic Testing Algorithm in Special Instructions.
Assessing risk of celiac disease
Most (90%-95%) patients with celiac disease have the DQ2 allele (encoded by DQA1*05 and DQB1*02), while the remainder have DQ8 (encoded by DQA1*03:01 and DQB1*03:02). Rare exceptions to these associations have been occasionally seen. In 1 study of celiac disease, only 0.7% of patients with celiac disease lacked the HLA alleles mentioned above.
It is important to realize that these genes also are present in about 20% of people without celiac disease. Therefore, the mere presence of these genes does not prove the presence of celiac disease or that genetic susceptibility to celiac disease is present.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
No significant cautionary statements
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
An interpretive report will be provided.
Clinical References Provides recommendations for further in-depth reading of a clinical nature
Polvi A, Arranz E, Fernandez-Arequero M, et al: HLA-DQ2-negative celiac disease in Finland and Spain. Hum Immunol 1998 Mar;59(3):169-175