Potential of the hepatic transcriptome expression profile of the striped seabream (Lithognathus mormyrus) as an environmental biomarker

The potential of an hepatic transcriptome expression profile, evaluated in a sentinel feral fish, to serve as an environmental biomarker was examined. Gene expression profiles of individuals of Lithognathus mormyrus were examined using a cDNA microarray and were correlated to the set of environmental exposure conditions at their site and date of collection. The clusters of individual gene expression profiles were reasonably related to the fish samples and several sample-specific clusters of genes, designated gene signatures of the sample, were determined. The relationship between transcriptome expression and the fish samples indicated a potential for their utilization as an environmental biomarker. Ten fish were sampled at each of two sites (Dor, Israel and Haifa, Israel) each of two years (2007 and 2008) for a total of 40 fish. All fish were hybridized to a common reference RNA population using a dye-swap design. Hence, each fish was hybridized twice vs. the reference RNA. The reference RNA was an equalized pool of the RNAs from all 10 fish comprising sample D7.