Synonym: fluorescent in situ hybridization

A technique used to identify the presence of specific chromosomes or chromosomal regions through hybridization (attachment) of fluorescently-labeled DNA probes to denatured chromosomal DNA. Examination under fluorescent lighting detects the presence of the hybridized fluorescent signal (and hence presence of the chromosome material) or absence of the hybridized fluorescent signal (and hence absence of the chromosome material).