ZytoLight^® SPEC ROS1 Dual Color Break Apart Probe

The ZytoLight^® SPEC ROS1 Dual Color Break Apart Probe (PL101) is a direct-labeled FISH probe for the qualitative detection of translocations of the human ROS1 gene at 6q22.1 in formalin-fixed, paraffin-embedded specimens, using fluorescence in situ hybridization (FISH). The probe is intended for use with the ZytoLight FISH-Tissue Implementation Kit.

ZytoLight^® probes enable the precise identification of genetic abnormalities, including translocations, deletions, amplifications, and chromosomal aneuploidies, in formalin-fixed, paraffin-embedded (FFPE) tissue sections or cytology specimens, without the need for additional antibody-based detection.

Components

The ZytoLight SPEC ROS1 Dual Color Break Apart Probe comprises:

• ZyGreen (excitation 503 nm/emission 528 nm) labeled polynucleotides (~10.0 ng/µl), targeting sequences mapping in 6q22.1* (chr6:116,912,298-117,627,255) proximal to the ROS1 breakpoint region;
• ZyOrange (excitation 547 nm/emission 572 nm) labeled polynucleotides (~4.5 ng/µl), targeting sequences mapping in 6q22.1* (chr6:117,659,135-117,871,701) distal to the ROS1 breakpoint region;
• Formamide based hybridization buffer

*according to Human Genome Assembly GRCh37/hg19


Principle


The fluorescence in situ hybridization (FISH) method enables the identification and visualization of particular nucleic acid sequences within cell samples. DNA fragments labeled with fluorescent dyes, known as FISH probes, are co-denatured with their complementary target DNA strands in the sample and then allowed to hybridize. Following hybridization, non-specific and unbound probe fragments are removed through stringency washes. The DNA is then counterstained with DAPI, and the hybridized probes are detected using a fluorescence microscope equipped with filters matched to the specific fluorochromes used to label the FISH probes.

This probe is intended for use in formalin-fixed, paraffin-embedded specimens, to qualitatively detect translocations of the human ROS1 gene at 6q22.1, via FISH.

Using suitable filter sets, the probe hybridization signals appear green near the ROS1 breakpoint region and orange away from it.

• Normal scenario: in normal cells during interphase or cells without a ROS1 gene region translocation, two green/orange fusion signals are observed.
• Aberrant scenario: one translocated ROS1 gene region is shown by one separate green and orange signal each. Isolated green signals are caused by deletions away from the ROS1 breakpoint region or due to unbalanced translocations affecting this chromosomal region.

Overlapping signals may appear yellow.

ZytoLight is a registered trademark of ZytoVision GmbH in Germany