Detection of chromosomal abnormalities by comparative genomic hybridization.
OBJECTIVE
Comparative genomic hybridization (CGH) is a modified in-situ hybridization technique. In this type of analysis, two differentially labeled genomic DNAs (study and reference) are cohybridized to normal metaphase spreads or to microarray. Chromosomal locations of copy number changes in the DNA segments of the study genome are revealed by a variable fluorescence intensity ratio along each target chromosome. Thus, CGH allows detection and mapping of DNA sequence copy differences between two genomes in a single experiment.


RESULTS
Since its development, comparative genomic hybridization has been applied mostly as a research tool in the field of cancer cytogenetics to identify genetic changes in many previously unknown regions. It is also a powerful tool for detection and identification of unbalanced chromosomal abnormalities in prenatal, postnatal and preimplantation diagnostics.


CONCLUSIONS
The development of comparative genomic hybridization and increase in resolution analysis by using the microarray-based technique offer new information on chromosomal pathologies and thus better management of patients.
Lapierre
Jean-Michel
JM
Service d'Histologie-Embryologie-Cytogénétique, Hôpital Necker-Enfants Malades, Paris bService de Biologie du Développement et de la Reproduction-Cytogénétique, Hôpital Antoine Béclère, Clamart, France. jm_lapierre@yahoo.fr
Tachdjian
Gérard
G
D002869:Chromosome Aberrations / Q000196:embryology*; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis / Q000235:genetics; D015894:Genome, Human; D006801:Humans; D009693:Nucleic Acid Hybridization / Q000379:methods*; D020411:Oligonucleotide Array Sequence Analysis; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods