ZytoLight^® SPEC EWSR1 Dual Color Break Apart Probe

The ZytoLight SPEC EWSR1 Dual Color Break Apart Probe (PL55) is a direct-labeled FISH probe designed for the qualitative detection of translocations involving the human EWSR1 gene at 22q12.2 in formalin-fixed, paraffin-embedded (FFPE) specimens. It is intended for use with the ZytoLight FISH-Tissue Implementation Kit.

Principle:

The fluorescence in situ hybridization (FISH) technique detects and visualizes specific nucleic acid sequences using fluorescently-labeled DNA fragments (FISH probes) that co-denature and hybridize with complementary target DNA strands. After stringent washing to remove unbound fragments, the hybridized probes are visualized with a fluorescence microscope equipped with specific excitation and emission filters.In this assay, directly labeled FISH probes co-denature with target DNA, hybridize with complementary sequences, and undergo stringent washing and DAPI counterstaining. Ten microliters of probe is applied to pretreated formalin-fixed, paraffin-embedded (FFPE) sections, denatured at 75 °C for 10 minutes, and hybridized overnight at 37 °C. Separate green and orange signals indicate EWSR1 rearrangements.

Components:

ZytoLight^® SPEC EWSR1 Dual Color Break Apart Probe comprises:

• ZyGreen labeled polynucleotides (excitation 503 nm/emission 528 nm), targeting sequences distal to the EWSR1 breakpoint region on chromosome 22 (22q12.2).
• ZyOrange labeled polynucleotides (excitation 547 nm/emission 572 nm), targeting sequences proximal to the EWSR1 breakpoint region on chromosome 22 (22q12.1).
• Formamide-based hybridization buffer.

For the qualitative detection of translocations involving the human EWSR1 gene at 22q12.2 by fluorescence in situ hybridization (FISH)

The probe is designed for qualitative detection of rearrangements at the EWSR1 gene locus (22q12) in formalin-fixed, paraffin-embedded (FFPE) tissue specimens by FISH. It is used in combination with the ZytoLight^® FISH-Tissue Implementation Kit for specimen pretreatment (dewaxing, proteolysis), denaturation/hybridization, and post-hybridization processing (washing, counterstaining).

In a normal interphase nucleus without translocations involving the 22q12.1-q12.2 region, two orange and two green signals are expected. In cases of translocation, separate green and orange signals will be observed, indicating the affected EWSR1 gene region. Unexpected signal patterns should be further investigated.

ZytoLight is a registered trademark of ZytoVision GmbH in Germany