Conventional cytogenetics, the study of chromosomes by G bands, is used for karyotype analysis of tumor cells. This method is complemented with the more sophisticated molecular cytogenetic techniques, which enable identification of balanced and unbalanced chromosome abnormalities.
Conventional cytogenetic study requires a sufficient number of high-quality metaphases and cannot detect submicroscopic changes or chromosomal rearrangements, which implicate chromosome areas with similar analysis of bands. Therefore, the conventional study is complemented with other techniques such as fluorescence in situ hybridization (FISH), multiplex-fluorescence in situ hybridization (M-FISH), and comparative genomic hybridization (CGH). These techniques can be used to rule out cryptic or submicroscopic anomalies in normal karyotypes, identify marker chromosomes, and enhance the study of anomalies present in complex karyotypes.
FISH with centromeric or locus-specific probes enables aneuploidy analysis and determines specific chromosomal rearrangements in interphase cells, imprints, and paraffin-embedded material.
To perform these techniques, we have a comprehensive panel of FISH probes, as well as bright field and fluorescence microscopes linked to image analysis systems.