ZytoLight^® SPEC TP53/CEN 17 Dual Color Probe

The ZytoLight^® SPEC TP53/CEN 17 Dual Color Probe is a direct-labeled FISH probe designed for the qualitative detection of deletions of the TP53 (tumor protein 53) gene and detection of chromosome 17 alpha satellites in formalin-fixed, paraffin-embedded (FFPE) tissue sections or cytologic specimens using Fluorescence in situ Hybridization (FISH), without the need for secondary antibody detection. This probe is intended for use alongside ZytoLight^® FISH Implementation Kits.


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 TP53/CEN 17 Dual Color Probe comprises:

• ZyOrange (excitation 547 nm/emission 572 nm) labeled polynucleotides (~4.5 ng/µl), targeting sequences mapping in 17p13.1* (chr17:7,495,749-7,663,022) harboring the TP53 gene region;
• ZyGreen (excitation 503 nm/emission 528 nm) labeled polynucleotides (~4.5 ng/µl), targeting sequences mapping in 17p11.1-q11.1 specific for the alpha satellite centromeric region D17Z1 of chromosome 17;
• 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 cytologic or formalin-fixed, paraffin-embedded specimens to qualitatively detect human TP53 gene deletions as well as the detection of chromosome 17 alpha satellites, via FISH.

Using suitable filter sets, the hybridization signals for the probe show as orange for the TP53 gene region and green for CEN 17.
Normal scenrio: in a normal cell during interphase, or in cells without a deletion in the TP53 gene region, two orange and two green signals are visible.
Aberrant scenario: if a deletion is present in the TP53 gene region, fewer orange signals will be seen. Deletions that impact only part of the TP53 gene region may produce orange signals that are smaller, but the overall signal pattern remains unchanged.
Overlapping orange and green signals may appear yellow.

ZytoLight is a registered trademark of ZytoVision GmbH in Germany