STR/VNTR Chimerism Analysis

Unique Aspects of Laboratory Testing

  • Sensitivity is routinely <1%.
  • Mixtures of DNA from each donor-recipient pair are used to ensure accurate sensitivity measurements.
  • A standard curve is prepared using DNA from the donor and recipient to detect preferential amplification of alleles. If preferential amplification is observed, the reported values are corrected using a standard curve.
  • Testing is available for cell subsets. Purity of subsets is determined using flow cytometry.
  • Two testing methods are available.
  • Consultation is available for test selection and interpretation of results.

Standard STR/VNTR testing

Tests

Informative loci (required before first standard assay)

Indications

  • To monitor engraftment after
    allogeneic BMT*
  • To detect relapse after allogeneic BMT*
  • Maternal engraftment
  • Genetic identity

*Monozygotic twins excluded

Methods

Amplified STR/VNTR alleles are quantified using an automated nucleotide sequencer. Cell subsets are prepared using magnetic particles. Purity of subsets is determined using flow cytometry.

Turn Around Time (arrival before 10am)

Routine test results in 3-10 business days*

STAT testing in 1-3 business days*

*Additional 2-5 days if informative loci
required

STR/VNTR Identity Testing

Tests

Identity testing panel

Indications

  • To determine genetic identity
  • To distinguish between monozygotic and dizygotic twins
  • To detect sample exchanges

Methods

STR/VNTR alleles for 12 loci located on different chromosomes are determined.

Turn Around Time (arrival before 10am)

Routine test results in 3-10 business days

STAT testing in 1-3 business days

STR/VNTR tests can be performed for the following cell subset

  • PBMC (peripheral blood mononuclear cells)
  • CD3 (T cells )
  • CD14/15 (myeloid lineage)
  • BMMC (bone marrow mononuclear cells)
  • CD19 (B cells)
  • CD71 (early erythroid)
  • CD34 (progenitor cells)
  • CD56 (NK cells)
  • Others upon request

 

 

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