[Rapid in situ detection of chromosome 21 by the PRINS technique].

The PRINS technique has been used to rapidly detect chromosomes 21 in both metaphases and interphase nuclei. A specific labeling was obtained in preparations from lymphocytes and amniotic fluid cells. The method is based on annealing of specific oligonucleotide primers and subsequent primer extension by a Taq DNA polymerase. PRINS is an interesting alternative to in situ hybridization for cytogenetic diagnosis and physical mapping.