DISCLAIMER: This link was displayed at 09:12:47 29/11/2021 and expires on 04/12/2021 if printed.

Go to http://testguide.adhb.govt.nz/EGuide/ for more information.

T Cell Receptor Gene Rearrangement Clonal Analysis
Short Description : T cell receptor gene rearrangement
Also known as : [TCR gene rearrangement]


DNA/RNA
Test performed by: LabPLUS - Dept. Diagnostic Genetics - Molecular Haematology


Specimen Collection

Note: All samples should be forwarded to LabPlus at room temperature within 24hours.


CPD4 mL CPD Blood (Preferred)
EDTA4 mL EDTA Blood
EDTA2 mL EDTA Bone Marrow
CPD2 mL CPD Bone Marrow
Paraffin block Tissue
Tissue
Turnaround Time: Within 2 weeks, 4 days

Reporting may be delayed in specific cases due to complexity. Please contact the lab for more information.


Diagnostic Use and Interpretation

This test is used to detect the presence of a monoclonal T cell population in a blood or tissue samples.

Note:   Although accurate in the majority of cases, molecular data should never be used in isolation to establish a diagnosis. The clinical setting, morphological findings and other ancillary tests should always be used in the final interpretation.

See also:

Immunoglobin Gene Rearrangement Analysis


Contact Information

To contact the Molecular Haematology team please call:

Auckland City Hospital   (09) 307 4949
Lablink   ext 22000
Prof. Peter Browett (Haematologist)     ext 9090-86281
Nikhil Ghallayan (Section Leader)   ext 22006
Molecular Haematology Lab   ext 22005

For more inforamtion about the Molecular Haematology service at LabPLUS:

Molecular Haematology information page




Information on T-Cell Receptor Gene Rearrangement Analysis:

During normal T cell development rearrangement processes occur in the T cell receptor (TCR) gene. The structure of the TCR gene consists of constant (C), joining (J) and variable (V) regions. Variability in structure is generated by a process of rearrangement of the DNA which involves splicing out and recombination of DNA segments. This process results in each T cell having its own specific combination of V and J segments which forms the basis of TCR diversity. Each cell has a characteristic rearrangement pattern which is present in all the progeny, therefore a clonal population consists of cells with the same pattern. The Southern blot technique is the 'gold-standard' for distinguishing between monoclonal and polyclonal lymphoproliferative disorders but this technique is time-consuming, requires large amounts of high-quality DNA and is technically difficult. PCR-based assays, which do not have these limitations, may be used instead. Most importantly, the PCR based assay can be used on paraffin-block extracted DNA samples, enabling analysis of histologically relevant samples.

PCR analysis of the TCRgamma gene recombination process may be used to asses T cell clonality as the rearrangement occurs in the majority of T cell neoplasms (irrespective of whether a functional TCRgamma receptor is expressed). Monoclonal TCRgamma rearrangements have been found in up to 90% of T cell neoplasms using the PCR method described below. Note, however, that 10-30% of T-cell malignancies may be missed by this method.  


Last updated at 11:48:27 18/03/2021