PT  - JOURNAL ARTICLE
AU  - M M Weiss
AU  - M A Hermsen
AU  - G A Meijer
AU  - N C van Grieken
AU  - J P Baak
AU  - E J Kuipers
AU  - P J van Diest
TI  - Comparative genomic hybridisation.
AID  - 10.1136/mp.52.5.243
DP  - 1999 Oct 01
TA  - Molecular Pathology
PG  - 243--251
VI  - 52
IP  - 5
4099  - http://mp.bmj.com/content/52/5/243.short
4100  - http://mp.bmj.com/content/52/5/243.full
SO  - Mol Pathol1999 Oct 01; 52
AB  - Comparative genomic hybridisation (CGH) is a technique that permits the detection of chromosomal copy number changes without the need for cell culturing. It provides a global overview of chromosomal gains and losses throughout the whole genome of a tumour. Tumour DNA is labelled with a green fluorochrome, which is subsequently mixed (1:1) with red labelled normal DNA and hybridised to normal human metaphase preparations. The green and red labelled DNA fragments compete for hybridisation to their locus of origin on the chromosomes. The green to red fluorescence ratio measured along the chromosomal axis represents loss or gain of genetic material in the tumour at that specific locus. In addition to a fluorescence microscope, the technique requires a computer with dedicated image analysis software to perform the analysis. This review aims to provide a detailed discussion of the CGH technique, and to provide a protocol with an emphasis on crucial steps.