Abstract

PRINCIPLE & TECHNIQUE OF COMPARATIVE GENOMIC HYBRIDIZATION

*Dr. Alka Chahar, Dr. Naveen Chahar and Dr. Arpita Kabiraj

Abstract

Comparative genomic hybridization (CGH) is a molecular cytogenetic method for the detection and mapping of chromosomal gains and losses. These techniques are serves to provide with essential information in cases pertaining to clinical applications in oncology and medical genetics and also basic evidence on fundamental characteristics of genome structure. It has been applied primarily as a research tool in the field of cancer genetics. The technique is applicable in clinical genetics as it helps in detecting the origin of extra or missing chromosomal material and provides a wide screening for unbalanced aberrations. Tumor DNA is labelled with a green fluorochrome, and is consequently mixed with red labelled normal DNA. This is then hybridized to normal human metaphase preparations. The green to red fluorescence ratio signifies loss or gain of genetic material in the tumor at that specific locus. Thus, this review provides a comprehensive explanation of the CGH technique.

Keywords: Fluorochrome; DNA microarray; Genome; Hybridization.