COMPARATIVE GENE-EXPRESSION PROFILING BY OLIGONUCLEOTIDE FINGERPRINTING

The use of hybridisation of synthetic oligonucleotides to cDNAs under high stringency to characterise gene sequences has been demonstrated b y a number of groups. We have used two cDNA libraries of 9 and 12 day mouse embryos (24 133 and 34 783 clones respectively) in a pilot study to characterise expressed genes by hybridisation with 110 hybridisati on probes. We have identified 33 369 clusters of cDNA clones, that ran ged in representation from 1 to 487 copies (0.7%). 737 were assigned t o known rodent genes, and a further 13 845 showed significant homologi es. A total of 404 clusters were identified as significantly different ially represented (P < 0.01) between the two cDNA libraries. This stud y demonstrates the utility of the fingerprinting approach for the gene ration of comparative gene expression profiles through the analysis of cDNAs derived from different biological materials.