Genotype HLA associated with Coeliac Disease

Clinical information

Diagnostic Utility:

90% of patients with celiac disease have the HLA-DQ2 molecule, a heterodimer formed by the HLA-DQA1*05 and DQB1*02 alleles. This strong association means that determining the DQ2 genotype serves as a diagnostic test when other tests are not conclusive. In the case of DQ8, it is present in 5% of celiacs and its determination is made by detecting the presence of the DQB1*0302 allele. The other 5% of patients with celiac disease have one of the 2 genes that form DQ2, but do not have the complete heterodimer.

Method:

Genotyping of the HLA-DQ2 (alleles DQA1*05/DQB1*02) and DQ8 (allele DQB1*0302) antigens by real-time PCR with FRET hybridization probes.

Reference Values

A result with a Ct (cycle threshold) of less than 35 cycles is considered positive. In the genotyping of the HLA-DQ2 and DQ8 antigens, the possible results are: positive or negative for DQB1*02, positive or negative for DQB1*03:02 (DQ8), and positive or negative for DQA1*05.

It has been observed that depending on the genotype, there is a differential risk range of association with Celiac Disease, from highest to lowest risk: DQ2/DQ2 individuals, DQ2/other, DQ8/other, and finally those who only have one of the 2 alleles that form DQ2.

Diagnostic Algorithm:

Not applicable.

Turnaround Time:

15 working days.

Specimen information

Sample: Whole blood
Tube: 4 ml EDTA K3 tube
Minimum volume: 500µl.

Stability:

• In refrigeration: 2 weeks.
• At -20ºC: from 2 weeks onwards.

Transport instructions: Preferably at room temperature

Reason for rejection: Coagulated sample.

Administrative information

BST Code: LRD2055
Test Description: HLA Genotype associated with Celiac Disease
Synonyms: Not applicable.
Section: Histocompatibility and Immunogenetics
BST Rate: Check the updated rates here.
Profiles: Not applicable.

References

Manual dels "Standards for Histocompatibility Testing" de l'EFI (darrera versió).

Quality

BST holds ISO 9001, ISO 14001, and OSHAS 18001 quality certifications, as well as the European Excellence 500+ seal. BST is accredited by CAT, JACIE-FACT, FACT-NETCORD, and EFI, and complies with Good Manufacturing Practice (GMP) and Good Distribution Practice (GDP) guidelines.