Table 2.

Advantages and limitations of molecular cytogenetic analysis

Advantages

Can be performed on metaphase or interphase cell preparations (fresh, frozen, or paraffin-embedded material)

Can localize anomaly in specific cells or tissue types

Can provide results when tissue is insufficient or unsatisfactory for cytogenetic analysis, when conventional cytogenetics has failed to yield results, or when cryptic rearrangements are present

Diagnostically useful. Sensitive and specific

Rapid turn-around time

Limitations

More targeted approach; not screening tool (generally requires prior knowledge of anomaly of interest)

Exceptions are CGH and SKY

Still a relatively gross approach when contrasting other molecular approaches capable of detecting single base mutations

Number of commercially available probes is limited

Requires fluorescence microscopy (signal fading)

Interpretation may be challenging when analyzing suboptimal specimens (i.e., background fluorescence or autofluorescence, particularly with formalin-fixed, paraffin-embedded material)

FISH nomenclature not consistent among laboratories

CGH, comparative genomic hybridization; SKY, spectral karyotyping