The CGH Method
Equal amounts of biotin-labeled tumor DNA and digoxigenin-labeled normal
reference DNA were hybridized to normal metaphase chromosomes.
The tumor DNA is visualized with fluorescein (FITC) and the normal DNA
with rhodamine (TRITC) and detected in a fluorescence microscope.
The images are captured by a CCD-camera and evaluated with a special
image analysis program.
The signal intensities of the different fluorochromes are quantitated as
gray levels along the single chromosomes.
The over-and underrepresented DNA segments are quantified by computation
of FITC/TRITC ratio images and average ratio profiles.
CGH