The Principles of Clinical Cytogenetics - Extra Materials - Springer

Fluorescence In Situ Hybridization 481
Fig. 17. Software interface of a CGH analysis system, showing the gain and loss profiles of the chromosomes.
See text for details. (Courtesy of Applied Imaging.)
of colors used. In order, therefore, to “paint” each of the 24 human chromosomes a different color,
five different fluorophores are needed. Specific computer software analyze the acquired data from
the probes and pseudocolors the chromosomes for analysis (the multiple colors can only be detected
and analyzed by utilizing such software). This type of analysis is especially useful for complex rearrangements,
such as those seen in neoplastic disorders and solid tumors (see center cover image). As
described earlier, this technology is also very useful for determining the origin of duplications and
marker chromosomes, or for detecting cryptic rearrangements (see bottom cover image).
mBAND Analysis
Multicolor banding (87) uses chromosome specific mixtures of partial chromosome paints that are
labeled with various fluorochromes. A computer program analyzes metaphase chromosome data and
produces a pseudocolored, banded karyotype with an estimated resolution of 550 bands, regardless of
chromosome length. This methodology is advantageous for the determination of breakpoints and the
analysis of intrachromosomal rearrangements (see Fig. 20) and can be particularly useful in preparations
with shorter chromosomes.
Fiber Fish
Fiber FISH is a technique that is almost entirely used for research. This technology allows the
chromosomes to be stretched out and elongated (88). The probes are applied and can be physically