HLA-DQB1 High-Resolution Typing

Clinical information

Diagnostic Utility:

High-resolution HLA typing allows us to determine the HLA typing at the allelic level (4 digits) of:

• Patients candidates for hematopoietic stem cell transplantation.
• Identical family members of patients candidates for hematopoietic stem cell transplantation.
• Voluntary donor registry.
• Expansion of HLA typing in voluntary donors.
• Registry and verification of umbilical cord blood units.
• Pre-transplant confirmation of donor and recipient.

Method:

The PCR-NGS technique (Long strategy and Short strategy) allows high-resolution HLA typing of HLA class I and II genes. This technique consists of several phases: amplification of the HLA genes of interest by PCR, library preparation, sequencing, and result analysis. With the Long strategy (long fragments), sequencing of the entire gene is obtained, while with the Short strategy (short fragments), exons 2, 3, and 4 of the HLA-A, -B, and -C genes are sequenced, as well as exons 2 and 3 of the HLA-DRB1, -DQB1, -DPB1, -DQA1, and -DPA1 genes.

The PCR-SBT technique allows high-resolution HLA typing of an isolated HLA gene. This technique consists of two phases: amplification of the exons of the HLA genes of interest by PCR and sequencing reaction of the amplified products. Finally, the sequences are analyzed by electrophoresis. Exons 2 and 3 of the HLA-DQB1 gene are sequenced.

Reference Values

With high-resolution typing, for each HLA gene, two results are obtained, for example: HLA-DQB1*02:01 DQB1*03:01.

Diagnostic Algorithm:

Not applicable.

Turnaround Time:

The turnaround time in high-resolution HLA typing depends on the origin of the sample:

• Patient or family members of patient candidates for hematopoietic stem cell transplantation (20 working days).
• Voluntary donor registry (20 working days).
• Expansion of HLA typing in voluntary donors (10 working days).
• Registry of umbilical cord blood units (20 working days).
• Verification of umbilical cord blood units (20 working days).
• Pre-transplant confirmation of donor and recipient (20 working days).

Specimen information

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

Stability:

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

Transport instructions: Preferably at room temperature

Reason for rejection: Clotted sample

Administrative information

BST Code: LRD2011
Test Description: High-resolution HLA-DQB1 typing
Synonyms: High HLA-DQB1
Section: Histocompatibility and Immunogenetics
BST Rate: Check the updated rates here.

Profiles:

The high-resolution HLA-DQB1 test is included in the "High-resolution HLA Complete Typing" profile (see table).

References

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