PML::RARA Detection by RT-PCR, Quantitative

Last Literature Review: January 2026 Last Update:

Use to detect and quantitate PML::RARA fusion transcripts in individuals with acute promyelocytic leukemia. 

Use to monitor minimal residual disease (MRD) in patients with a known history of PML::RARA fusion transcripts and assess the risk of disease relapse. 

This test detects isoforms bcr1, bcr2, and bcr3; it does NOT identify which transcript is detected.

Testing for PML::RARA fusion transcripts may be useful as part of the evaluation of suspected acute promyelocytic leukemia.  PML::RARA testing can be used to monitor for minimal residual disease (MRD).  These tests use reverse transcription polymerase chain reaction (RT-PCR) to detect if a fusion transcript is present.

Genetics

PML::RARA fusion type A (short, S-form, bcr-3), type B (long, L-form, bcr-1), and type B variant (variable, V-form, bcr-2)

Test Interpretation

Analytic Sensitivity/Specificity

Analytic specificity: >99% above the limit of quantitation (≥0.0005 normalized copy number [NCN])

Limit of quantitation: ≥0.0005 NCN

Limit of detection: 1/10,000 t(15;17) positive cells

Limitations

  • This assay does not identify which transcript is detected.
  • Levels can only be reliably compared if using the same laboratory and same sample type each time.
  • This assay will only detect PML::RARA fusions and will not detect fusions from the less common RARA fusion gene partners or rare variants not included in the isoforms tested.

References