Isolation and characterisation of a panel of cosmids which allows unequivocal identification of chromosome deletions involving the RB1 gene using fluorescence in situ hybridisation.

A series of cosmids covering the majority of the RB1 gene have been isolated from a flow sorted human chromosome 13 specific library. Using fluorescence in situ hybridisation these cosmids were all shown to hybridise to the 13q14 region but not to chromosomes known to carry subband deletions involving the RB1 gene. This panel of cosmids, therefore, can be used objectively for identification of RB1 gene deletions in tumour and normal cells.