40
EIGIL KJELDSEN and STEEN K0LVRAA
Summary
An overall summary of the advantages ofFISH techniques is listed in Table
5. The listed advantages clearly make FISH a serious competitor to traditional banding techniques. Whether FISH in the future will replace traditional cytogenetic techniques is at present difficult to say, and will to some
extent depend on the future developments in FISH-technology. The following chapters in the book will give numerous examples of these future
developments.
Table 5. Several advantages apply to the use of FISH
Sensitivity
In clinical cytogenetics and oncology FISH has the potential to detect
cryptic chromosomal deletions and rearrangements, which cannot be
detected by conventional banding methods. In microbiology it is
possible to detect the presence of microorganisms at an early stage.
RNA expression from endogenous or exogenous genes can be detected.
Specificity
By choosing a particular probe or probes and relevant methodology,
chromosomal material of unknown or uncertain origin can be identified, and in research the chromosomal localization of specific DNA
fragments/sequences can be achieved.
Efficiency
FISH also allows rapid screening for large number of metaphases for
one or more target sequences. Specific genetic information is obtained
for individual cells and can be correlated to other types of information
as FISH can be combined with immunophenotyping of individual cells.
Applicability Many tissues and types of cells are not directly accessible for conventional cytogenetic methods, but can be examined by FISH analysis
on interphase nuclei. Thus, examination of resting cells in interphase
may be a much larger and potentially more informative cell population. Also when a new gene or DNA sequence is cloned it is relatively
easy to utilize it as a diagnostic tool.
Economy
Because of the simplicity of the basic FISH concept, the technique can
now relatively easily be established in almost any laboratory.
Furthermore, after establishment of the equipment which is relatively
costly, each assay is rather inexpensive. The development of CGHanalysis and 24-color karyotyping has reduced the time and laborconsumption in situations where FISH is used without any knowledge
of the chromosomal aberration.
EIGIL KJELDSEN and STEEN K0LVRAA
Summary
An overall summary of the advantages ofFISH techniques is listed in Table
5. The listed advantages clearly make FISH a serious competitor to traditional banding techniques. Whether FISH in the future will replace traditional cytogenetic techniques is at present difficult to say, and will to some
extent depend on the future developments in FISH-technology. The following chapters in the book will give numerous examples of these future
developments.
Table 5. Several advantages apply to the use of FISH
Sensitivity
In clinical cytogenetics and oncology FISH has the potential to detect
cryptic chromosomal deletions and rearrangements, which cannot be
detected by conventional banding methods. In microbiology it is
possible to detect the presence of microorganisms at an early stage.
RNA expression from endogenous or exogenous genes can be detected.
Specificity
By choosing a particular probe or probes and relevant methodology,
chromosomal material of unknown or uncertain origin can be identified, and in research the chromosomal localization of specific DNA
fragments/sequences can be achieved.
Efficiency
FISH also allows rapid screening for large number of metaphases for
one or more target sequences. Specific genetic information is obtained
for individual cells and can be correlated to other types of information
as FISH can be combined with immunophenotyping of individual cells.
Applicability Many tissues and types of cells are not directly accessible for conventional cytogenetic methods, but can be examined by FISH analysis
on interphase nuclei. Thus, examination of resting cells in interphase
may be a much larger and potentially more informative cell population. Also when a new gene or DNA sequence is cloned it is relatively
easy to utilize it as a diagnostic tool.
Economy
Because of the simplicity of the basic FISH concept, the technique can
now relatively easily be established in almost any laboratory.
Furthermore, after establishment of the equipment which is relatively
costly, each assay is rather inexpensive. The development of CGHanalysis and 24-color karyotyping has reduced the time and laborconsumption in situations where FISH is used without any knowledge
of the chromosomal aberration.