Cosmid (unique sequence) probes bind to specific small segments of certain chromosomes.

These probes are useful in microdeletion studies, where the presence or absence of a region

of a chromosome can be diagnostic of certain syndromes or abnormalities.

 

Example of microdeletion syndrome probes:

 

 

Further information:

http://www.slh.wisc.edu/cytogenetics/procedures/fish/index.php