PML/RARA TRANSLOCATION ASSAY By FISH

FISH (fluorescence in situ hybridization) uses fluorescently labeled DNA probes that bind specific chromosome regions to detect translocations and rearrangements. When probes hybridize to metaphase chromosomes or interphase nuclei, altered signal patterns reveal chromosomal breaks, fusions, or gene rearrangements. It’s commonly used in cancer diagnostics and genetic testing to rapidly and sensitively localize abnormal genes.

The FISH test for APL (acute promyelocytic leukemia) uses fluorescence in situ hybridization to detect the PML–RARA fusion gene from the t(15;17) chromosomal translocation. It gives rapid, specific confirmation by showing fusion signals in leukemic cells, guiding immediate treatment with ATRA and arsenic trioxide and aiding response monitoring. PCR is more sensitive for minimal residual disease but FISH is faster.

A positive FISH test in multiple myeloma means chromosomal abnormalities are detected in the malignant plasma cells. Specific changes (for example del(17p), t(4;14), t(14;16), or 1q gain) help classify risk, inform prognosis, and guide treatment choices. Results often prompt closer monitoring and may lead clinicians to use more aggressive or tailored therapy for high‑risk alterations.

The FISH (fluorescence in situ hybridization) test for leukemia is a laboratory technique that uses fluorescent probes to detect specific chromosomal abnormalities—translocations, deletions, or amplifications—in leukemia cells from blood or bone marrow. Results help confirm diagnosis, classify leukemia subtype, guide prognosis and targeted therapy decisions, and monitor residual disease. Turnaround is usually faster than conventional karyotyping.

Fluorescence in situ hybridization (FISH) is used to detect and localize specific DNA or RNA sequences within cells and tissue samples. It identifies chromosomal abnormalities (aneuploidy, translocations, deletions, amplifications), guides cancer diagnosis, prognosis and targeted therapy, aids prenatal and neonatal genetic testing, and can detect pathogens. FISH provides rapid, sensitive, and specific results on interphase nuclei and fixed tissue sections.

Yes. Fluorescence in situ hybridization (FISH) can identify chromosomal translocations by using labeled DNA probes that bind specific chromosome regions; it reveals rearrangements, fusion genes, deletions, and amplifications in interphase or metaphase cells. FISH is widely used in cancer and diagnostic labs, but it detects only targeted or known abnormalities and has limited resolution for very small or novel rearrangements.