FAST, SENSITIVE MULTICOLOR DETECTION OF NUCLEIC-ACIDS IN-SITU BY PRIMED IN-SITU LABELING (PRINS)

PRimed IN Situ labeling (PRINS) has become an alternative to tradition al fluorescence in situ hybridization (FISH) methods for detection of nucleic acids in situ. PRINS is based on sequence-specific annealing i n situ of an unlabeled DNA probe. The probe serves as a primer for cha in elongation in situ, catalyzed by a suitable.DNA polymerase that use s labeled nucleotides as substrate. The fact that the probe is unlabel ed means that high probe concentrations can be utilized, making the hy bridization very fast. We describe here a fast method for detection of three different target sequences visualized in different colors with PRINS. An advantage, relative to FISH, is that even probes with differ ent melting temperatures can be detected in the same metaphase with op timal stringency for each probe.