Abstract: To present a brief review on primed in situ labeling (PRINS) methods and applications.PRINS is a new molecular cytogenetic method and could serve as an alternative to, as well as a complementary approach to fluorescence in situ hybridization (FISH) for chromosome studies.PRINS can provide fast (1-4 h),reliable,and cost-effective results.Development of multi-color PRINS makes it possible to study several chromosome targets simultaneously.PRINS can detect repetitive(e.g.centromeric,telomeric or Alu repeats) and single copy sequences/genes,depending on the primers used.It is applicable to metaphase and interphase cells in postnatal,prenatal,or preimplantation diagnosis.PRINS has great potential in chromosome research and diagnosis,including:①identification of numerical aberrations(e.g.trisomies 21,13,and 18 and 45,X),②detection of chromosome markers,③rapid screening for subtelomere deletions,④diagnosis of microdeletion syndromes(e.g. Prader Willi/Angelman and DiGeorge/Velocardiofacial syndromes),⑤Chromosome studies in sperm,⑥preimplantation screening of common aneuploidies,and ⑦cancer cytogenetics.