Uncultured blood samples can be labeled by PRINS and ready for chromosome enumeration analysis 1 H after collection

We describe a rapid technique to determine numerical abnormalities of chromosomes that can be applied to slides prepared from fresh, uncultured blood samples. Primed in situ synthesis is a method that has previously been utilized as a rapid alternative to conventional fluorescence in situ hybridization for localizing repeated DNA sequences on metaphase chromosomes and interphase nuclei prepared from cultured lymphocytes. By applying the technique to uncultured preparations from fresh blood, aneuploidy analysis can be completed in less than 3 h from the collection of the blood sample.