Samut Prakarn Region GuidesAfter hybridization, electronic imaging systems are used to catch and quantify the relative fluorescence intensities of all of the hybridized fluorophores. The resulting ratio of the fluorescence intensities is proportional to the ratio of the copy numbers of DNA sequences in the test and reference genomes. If the intensities of the fluorochromes are equal on one probe, this region of the patient’s genome is interpreted as having equal quantity of DNA in the test and reference samples; if there’s an altered Cy3:Cy5 ratio, this indicates a loss or a gain of the affected person DNA at that exact genomic region Taken from omparative genomic hybridization/media/File:Array CGH protocol. svgFISH has now become an essential tool for gene mapping and characterization of chromosome aberrations. Since the objective DNA continues to be intact, unlike in molecular genetic evaluation, advice is received without delay about the positions of probes relating to chromosome bands or to other hybridized probes. Using differentially categorised probes, chromosome aberrations on specific chromosomes or chromosomal regions can be easily described.