Chromosome microdissection is a recently developed molecular cytogenetic technique that has become increasingly important as a bridge connecting cytogenetics to molecular genetics. After a decade of effort, this approach has been developed into a useful and reproducible approach for several purposes, including1) the isolation of DNA from any cytogenetically recognizable region which can be used to generate DNA microclone libraries for molecular analysis and positional cloning (1 ,2 ) the generation of fluorescence in situ hybridization (FISH) probes for whole chromosome painting probes (3 ), and chromosome arm painting probes (4 ) for cytogenetic study; 3) combined with FISH, microdissection has been applied to detecte virtually any kind of visible chromosome rearrangements (5 ,6 ); and more recently, 4) microdissection combined with hybrid selection has been applied to identify genes associated with homogeneously staining regions (HSRs) in human cancers (7 ,8 ).
