b'TRG MRD Clonality Assay MRD TestsBackground Test Name Next-generation sequencing of the PCR products is Combinations of chemotherapy, radiation therapy andlocus become rearranged through the random deletionTRG MRD Clonality Assayused to identify DNA sequences specific to previously bone marrow transplantation are potentially curativeor insertion of nucleotides within the junctional region,identified clonal rearrangements detected at diagnosis. for several hematologic malignancies. However, in somegenerating specific and unique sequences within eachBioinformatics tools facilitate the detection of these-6Assay Type specific sequences present at MRD levels up to 1 x 10with patients, occult tumor cells exist and are thought to increaselymphocyte. Cancer cells that arise from alterations insufficient DNA input.the patients risk of relapse. 1These subclinical levels ofsingle lymphoid precursors acquire clonal TRG junctionalNext-Generation Sequencing (NGS) residual leukemia are termed minimal residual diseaseregions which can be used as tumor-specific markers. 2,3 For Research Use Only The assay typically requires a sample taken at diagnosis as (MRD) and can be evaluated using sensitive assays. well as the post-treatment follow-up samples. If the patient MRD detection by Next-Generation Sequencing hasThis test is performed by using the LymphoTrack Assayhas previously been tested by LabPMM for TRG clonality, The tracking of antigen-receptor gene rearrangementsdemonstrated utility in predicting clinical outcomesfrom Invivoscribe. Data is analyzed using the LymphoTrackno diagnostic sample is needed.for clonality analyses and MRD monitoring can be appliedand in generating clinically actionable results, allowingMRD Software (RUO).to virtually all patients. During early T-cell development,early intervention, confirmation of disease status prior to the germline variable (V), constant (C), and joining (J)transplant, and increased confidence in remission status.Indications for Testingfragments of the T Cell Receptor Gamma (TRG)Method DescriptionIdentify tumor-specific markers for post-treatmentTo track and identify previously detected TRG clonalmonitoring sequences in post-treatment follow-up samples, aMonitor and evaluate disease recurrencemultiplex master mix targeting the V and the J regionis used for PCR amplification.Interpretation TurnaroundSpecimenShippingSpecimen Time Requirements Conditions StabilityAn interpretive5 to 14 1-3 mL of peripheral Ambient or Cool; 2-8 C up report will bebusiness daysblood in EDTA do not freezeto 7 days priorissued indicating0.25-1 mL of bone marrow (peripheral blood or to testingwhether TRG MRDin EDTA bone marrow) was detected700-3500 ng of previouslyAmbient or frozen onisolated DNA dependingdry ice (isolated DNA)References on level of sensitivity required1. Rezuke WN et al. (1997) Molecular diagnosis of B- and T-cell lymphomas: fundamental principles and clinical applications. Clin Chem 43:1814-23.2.Gazzola A et al. (2014) The evolution of clonality testing in the diagnosis and monitoring of hematological malignancies. TherAdv Hematol. 5:35-47.3.Gonzlez D et al. (2007) Immunoglobulin gene rearrangements and the pathogenesis of multiple myeloma. Blood 110:3112-21. 46 LabPMM Services Catalog 2021|47'