Combined Binary Ratio Labeling-FISH (COBRA-FISH) (CAT#: STEM-MB-1182-WXH)

Brobes are ratio labeled with a pair of fluorochromes to distinguish, for example, five different targets based on their ratios. Hence, by pairwise-ratio labeling with three fluorochromes, sets of 12 ratio-labeled probes can be generated. T o increase multiplicity, the same three fluorochromes are used to ratio label additional sets of 12 probes in an identical fashion. These two sets are then discriminated by an additional spectrally distinct fluorochrome, referred to as the binary label.
Thus, by binary ratio labeling, 24 targets can be discriminated with only four fluorochromes (compared with five required for combinatorial labeling). The fifth fluorochrome is now available to label, for instance, an additional probe (bacterial artificial chromosome (BAC) or cosmid) against a specific DNA sequence.

Precise assessment of complex chromosomal rearrangements.
Precise chromosome separation and for rapid chromosome classification.
Permits gene and viral integration site mapping in the context of chromosome arm painting.

1. Generation and labeling of chromosome-painting probes.
2. Probe labeling.
3. Determination of DOL(dye-to-DNA ratio).
4. COBRA-FISH.
5. Imaging.

• Flow cytometer
• Fluorescence microscopy