Reference range(s)
The reference ranges listed below are valid on this date of April 19, 2024.
| Component | Age | Male Norm | Male Critical Low | Male Critical High | Female Norm | Female Critical High | Female Critical Low | Units | Add'l info |
|---|---|---|---|---|---|---|---|---|---|
| HLA-DQA1, Allele 1 | ALL | See report. | |||||||
| HLA-DQA1, Allele 2 | ALL | See report. | |||||||
| HLA-DQB1, Allele 1 | ALL | See report. | |||||||
| HLA-DQB1, Allele 2 | ALL | See report. | |||||||
| Celiac HLA Interpretation | ALL | BACKGROUND... Note1 |
Note1:
BACKGROUND INFORMATION:
CHARACTERISTICS: Celiac disease is a systemic autoimmune
disease of the gastrointestinal system caused by exposure to
cereal gluten in genetically susceptible individuals.
INCIDENCE: On average, 1 in 133 individuals in the United
States is affected.
INHERITANCE: Multifactorial.
CAUSE: The presence of either HLA-DQ2 or the HLA-DQ8
alleles in combination with dietary gluten.
CLINICAL SENSITIVITY: greater than 99 percent.
METHODOLOGY: Polymerase Chain Reaction/Massively Parallel
Sequencing, or Polymerase Chain Reaction/Sequence-Specific
Oligonucleotide Probe Hybridization.
ANALYTICAL SENSITIVITY AND SPECIFICITY: greater than 99
percent.
LIMITATIONS: Rare diagnostic errors may occur due to primer
site mutations. Other genetic and nongenetic factors that
influence celiac disease are not evaluated. In cases where an
HLA allele cannot be resolved unambiguously, the allele
assignment will be reported as the most common, based on
allele frequencies from the common, intermediate and well-
documented alleles catalogue version 3.0.0 (Hurley CK et al,
2020).
ALLELES TESTED: HLA-DQA1 and HLA-DQB1 alleles. Most celiac
disease patients (approximately 90 percent) carry HLA-DQ2.5
heterodimers encoded by HLA-DQA1*05 and HLA-DQB1*02
alleles. The remaining 5-10 percent of the patients carry HLA-
DQ8, encoded by HLA-DQB1*03:02 allele, most commonly in
combination with HLA-DQA1*03 alleles. A minority of patients
negative for the above genotypes may carry HLA-DQB1*02 but
without the DQA1*05 alpha chain, most commonly with
DQA1*02. The presence of the DQB1*02 allele in combination
with either DQ2.5 or DQ8 may further increase celiac disease
risk.
Stratified overall genetic risk for patients carrying the
celiac disease-associated HLA-DQ genotypes:
Genotype.............Risk*
DQ2.5 homozygous ....Very High (greater than 1:10)
DQ2.5 + DQB1*02......Very High (greater than 1:10)
DQ2.5 + DQ8..........High (greater than 1:20)
DQ8 homozygous.......High (greater than 1:20)
DQ8 + DQB1*02 (without DQA1*05)
.....................Intermediate (greater than 1:50)
DQ2.5 heterozygous...Intermediate (greater than 1:50)
DQ8 heterozygous.....At risk (greater than 1:100)
Population risk for unknown genotype......1:100
DQB1*02 (without DQA1*05).................Low
DQA1*05 (without DQB1*02).................Minimal
Negative for DQ2 and DQ8..................Not at risk
* Risk is provided from the references below, and defined
according to HLA allele combinations, considering a disease
prevalence of 1:100. However, these alleles are common
in the general population and the majority of individuals
positive for celiac-associated alleles do not develop the
disease. Detection of these alleles can support a clinical
diagnosis but should not be interpreted as diagnostic of
celiac disease.
References:
1. Megiorni F, Mora B, Bonamico M, et al. HLA-DQ and risk
gradient for celiac disease. Human Immunology.2009;70:55-59.
2. Pietzak MM, Schofield TC, McGinnis MJ, et al. Stratifying
risk for celiac disease in a large at-risk United States
population by using HLA alleles. Clinical Gastroenterology
and Hepatology. 2009;7:966-971.
3. Almeida LM, Gandolfi L, Pratesi R, et al. Presence of
DQ2.2 associated with DQ2.5 increases the risk for celiac
disease. Autoimmune Diseases, 2016. 2016:5409653.
4. Vader W, Stepniak D, Kooy Y, et al. The HLA-DQ2 gene dose
effect in celiac disease is directly related to the magnitude
and breadth of gluten-specific T cell responses.
PNAS. 2003;100:12390-12395.
DISCLAIMER INFORMATION:
This test was developed and its performance characteristics
determined by the Histocompatibility& Immunogenetics
laboratory at the University of Utah Health. It has not been
cleared or approved by the US Food and Drug Administration
(FDA). The FDA has determined that such clearance or approval
is not necessary. This test is used for clinical purposes.
It should not be regarded as investigational or for research.
Histocompatibility and Immunogenetics laboratory is certified
under the Clinical Laboratory Improvement Amendments of 1988
(CLIA-88) as qualified to perform high complexity clinical
laboratory testing.
See report..