Table 4. Comparisons of different techniques in cytogenetics
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Advantages
Disadvantages
Solution
CGH
Interphase nuclei FISH
Locus specific FISH probes
Telomeric
FISH probes
Multicolor
FISH, e.g. 24-color
karyotyping
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FISH painting - whole chromosome painting, arm-specific
painting, multicolor painting
Difficulties in identifying short
chromosome fragments
(e.g. markers) and complex
rearrangements, especially in low
quality chromosome preparations
Generation of meta- or proInterphase nuclei FISH CGH
phases in general requires cell
growth. Some times samples cannot
be grown (fixed pathology samples)
or time
is crucial (e.g. late amniocentesis)
Limited resolution, e.g.
microdeletions and other
subtle rearrangements
Cells in metaphase does not
always represent the total cell
population
Some knowledge on identity
of the abnormality in question
is required - not possible for
markers/ring chromosomes
or complex rearrangements
Cannot be used to screen for
unknown structural aberrations
Resolution
is 5-10
Mb
Nucleic acid arrays?
Structural balanced
rearrangements not identified
Small interstitial rearrangements Nucleic acid arrays?
cannot be identified
(amplifications etc)
Screening
of the whole genome
Specific identification of a
part of the genome
Rapid identification of
numerical aberrations in
non-dividing cells
Screening the whole genome
for amplifications or deletions
in non-viable cells
Screening the whole genome
in viable cells
Painting
FISH
Interphase FISH
24 color karyotyping
Conventional
banding (highor
low resolution)
CGH