b'IGH Clonality Assays Clonaltiy TestsClinical Information Test Name framework region 3, as well as the joining region, is used for PCR amplification. Next-generation sequencing of the Lymphoid cells are different from the other somatic cellsSince leukemia and lymphomas originate from theIGH FR1 clonality assay PCR products is used to identify DNA sequences specific to in the body as during development, the antigen receptormalignant transformation of individual lymphoid cells,IGH FR2 clonality assayclonal gene rearrangements. Bioinformatics tools facilitate genes of these cells undergo somatic gene rearrangement. 1 all leukemias and lymphomas generally share one orIGH FR3 clonality assaythe characterization of sequences present at greater than The human immunoglobulin heavy chain (IGH) gene locusmore cell-specific or clonal antigen receptor gene2.5% of the population. These sequences can be used to rearrangements. Clonality does not always implytrack specific clonal populations.on chromosome 14 (14q32.3) includes 46-52 functionalmalignancy; all results must be interpreted in the contextAssay Typeand 30 non-functional variable (V H ) gene segments, 27of all of the other available diagnostic criteria. Tests functional diversity (D H ) gene segments, and 6 functionalthat detect IGH clonal rearrangements are useful in theNext-Generation Sequencing (NGS) Indications for Testingjoining (J H ) gene segments spread over 1250 kilobases.characterization, monitoring, and treatment of B- andThis test is performed by using the LymphoTrack or dentify clonality in atypical lymphoproliferative During B-cell development, genes encoding the IGHImolecules are assembled from multiple polymorphic geneT-cell malignancies. LymphoTrack Dx Assay from Invivoscribe disorderssegments that undergo rearrangements and selection.Support a differential diagnosis between reactiveThese gene rearrangements of the variable, diversity andMethod Description lesions and hematologic malignanciesjoining segments generate V H -D H -J Hcombinations of uniqueAssign presumptive lineage in mature monoclonal length and sequence for each cell. 2,3 For detection of the vast majority of clonal IGH V H -J Hrearrangements, including the associated V H -J Hregionlymphoproliferative disorders DNA sequences, a multiplex master mix targeting theMonitor and evaluate disease recurrenceconserved framework region 1, framework region 2, or Interpretation TurnaroundSpecimenShippingStorage Time Requirements Conditions ConditionsAn interpretive report will be5 to 10 1-3 mL ofAmbient orRoom Temp issued indicating whetherbusiness daysperipheral blood inCool; do notup to 72 hoursevidence of clonality wasHeparin, EDTA orfreeze (peripheral2-8 C updetected. The report furtherACD blood or bone provides a summary of themarrow)to 7 days prior to testingtop 5 merged sequences,0.25-1 mL of bone including the % total reads,marrow in Heparin,Ambient or the rearrangement class andEDTA or ACD frozen on dry ice 500 ng of(isolated DNA)the sequence.previously isolated References DNA1.Tonegawa S (1983) Somatic Generation of Antibody Diversity. Nature 302:575-581.2. Trainor KJ et al. (1990). Monoclonality in B-lymphoproliferative disorders detected at the DNA level. Blood 75:2220-2222.3.JE Miller et al., Molecular Genetic Pathology (2013, 2nd ed.) Springer Science & Business Media 302.2.7.13 and 30.2.7.18.26 LabPMM Services Catalog 2020|27'