Abstract: The method of the present invention relates to a rapid procedure for detecting DNA in a cell, while preserving the morphology of the nucleus for analysis. The method comprises depositing a cell onto a polymeric membrane filter wherein the DNA contained in the cell is retained on the polymeric membrane filter and is available for binding with a fluorescently labeled nucleic acid probe, incubating the polymeric membrane filter with the labeled nulceic acid probe, and detecting the labeled nulceic acid probe wherein detection of the nulceic acid probe is indicative of the presence of the DNA. There are no separate permeabilization steps needed to permit the probes to enter the cell and hybridize to the DNA. The method is simple and quick and is applicable to the sample volumes found in clinical laboratories.