Test Code LAB1231913 Celiac Associated HLA-DQ Alpha 1 and DQ Beta 1 DNA Typing, Blood
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Reporting Name
Celiac Associated HLA-DQ TypingSpecimen Type
Whole Blood ACD-BOrdering Guidance
Cascade testing is recommended for celiac disease. Cascade testing ensures that testing proceeds in an algorithmic fashion. The following cascades are available; select the appropriate one for your specific patient situation.
-CDCOM / Celiac Disease Comprehensive Cascade, Serum and Whole Blood: complete testing including HLA DQ
-CDSP / Celiac Disease Serology Cascade, Serum: complete testing excluding HLA DQ
-CDGF / Celiac Disease Gluten-Free Cascade, Serum and Whole Blood: for patients already adhering to a gluten-free diet
To order individual tests, see Celiac Disease Diagnostic Testing Algorithm.
Specimen Required
Container/Tube: Yellow top (ACD Solution A or B)
Specimen Volume: 6 mL
Collection Instructions: Send whole blood specimen in original tube. Do not aliquot.
Reject Due To
| Extracted DNA | Reject |
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Whole Blood ACD-B | Refrigerated (preferred) | |
| Ambient | ||
Specimen Minimum Volume
3 mL
Special Instructions
Day(s) Performed
Monday through Friday
Specimen Retention Time
14 daysReport Available
3 to 8 daysReference Values
An interpretive report will be provided.
Useful For
Assessing risk of celiac disease
Testing Algorithm
The following algorithms are available:
-Celiac Disease Comprehensive Cascade Test Algorithm
-Celiac Disease Diagnostic Testing Algorithm
-Celiac Disease Gluten-Free Cascade Test Algorithm
CPT Code Information
81376 x 2-HLA Class II typing, low resolution (eg, antigen equivalents); one locus (eg, HLA-DRB1/3/4/5, -DQB1, -DQA1, -DPB1, or -DPA1), each
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| CELI | Celiac Associated HLA-DQ Typing | 94492-6 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| DQA | DQ alpha 1 | 94495-9 |
| DQB | DQ beta 1 | 53938-7 |
| CELIG | Celiac gene pairs present? | 48767-8 |
| CELIC | Interpretation | 69048-7 |
Method Description
LABType applies Luminex technology to the reverse sequence-specific oligonucleotide (SSO) DNA typing method. First, target DNA is polymerase chain reaction (PCR)-amplified using a group-specific primer. The PCR product is biotinylated, which allows it to be detected using R-phycoerythrin-conjugated streptavidin. The PCR product is denatured and allowed to rehybridize to complementary DNA probes conjugated to fluorescently coded microspheres. A flow analyzer identifies the fluorescent intensity of phycoerythrin on each microsphere. The HLA Class II allele or allele groups of the sample is determined by the positive and negative bead ID's using a computer software program. The assignment of the HLA typing is based on the reaction pattern compared to patterns associated with published HLA gene sequences.(Package insert: LABType SSO Typing. One Lambda; Version 04, 11/11/2019)
Supportive Data
This figure shows the risk gradient of tissue transglutaminase (tTG) IgA positivity according to the HLA-DQ haplotype combination. Compared with patients who had non-permissive HLA-DQ heterodimers, patients who had HLA-DQ2 homozygosity (HLA-DQ2.5/DQ2.5, HLA-DQ2.5/DQ2.2, or HLA-DQ2.2/DQ2.2) showed increased odds for tTG-IgA positivity (OR =96.9; 95% CI, 58.3–147.9, p < .0001). Patients with one copy of HLA-DQ2.5, or HLA-DQ2.5 heterozygotes, also have increased odds for developing tTG-IgA positivity (OR =36.8; 95% CI, 23.3–57.9, p < .0001). Interestingly, the odds for patients who were compound heterozygous for HLA-DQ2.5 and HLA-DQ8 (OR =42.3; 95% CI, 25.2–71.0, p < .0001) were similar to those for HLA-DQ2.5 heterozygotes. This suggests that a single HLA-DQ8 haplotype may not provide additional risk for tTG-IgA positivity. HLA-DQ8 carriers also showed increased odds for tTG-IgA positivity.(2)
Forms
If not ordering electronically, complete, print, and send Gastroenterology and Hepatology Test Request (T728) with the specimen.