The Notch signaling is an evolutionarily conserved signal transduction cascade that plays essential roles in a variety of developmental processes. In this study, we examined the mib mutants for defects in pancreas development using in situ hybridization and GFP expression analysis of pancreas-specific GFP lines, and carried out the global gene expression profile analysis of three different mib mutantalleles. Global expression profile analysis showed that there is a significant difference in gene expression profile of wild type and three mib mutant alleles. There are 91 differentially expressed genes that are common to all three mib alleles. Through detailed analysis of microarray data we have identified several previously characterized genes and some putative Notch-responsive genes involved in pancreas development, and validated theirexpression profile using real-time PCR and in situ hybridization. We propose that this study provides a useful resource of global gene expressionprofile in mib mutants, which will be helpful in identifying the function of novel genes involved in Notch signaling and Notch-responsive genesinvolved in a variety of developmental processes. Keywords: comparison of global gene expression in mib mutant and wild type embryos All samples were analysed on Zebrafish microarray chips generated at the Genome Institute of Singapore