Mapping of single-copy DNA sequences on human chromosomes by in situ hybridization with biotinylated probes: enhancement of detection sensitivity by intensified-fluorescence digital-imaging microscopy

摘要: Abstract Two single-copy DNA segments of 6 kilobases (kb) and 2.3 kb were labeled with biotin-labeled dUTP (Bio11-dUTP) hybridized to human chromosomes. These probes detected by immunofluorescence directly mapped on chromosomes using classical fluorescence microscopy a microchannel-plate-intensified video camera. By subsequent R-banding, the 6-kb 2.3-kb fragments precisely localized 18p11.3 band 22q11.2 band, respectively, in agreement previous results obtained radioactive probes. The adaptation intensification digital image processing (frame integration enhance signal-to-noise ratio linear contrast stretching) makes it possible detect very weak fluorescent spots This system allows high spatial resolution (less than 0.6 micron), even at low levels. efficiency specificity hybridization detection methodology give direct precise localization short sequences