Biomonitoring marine environmental quality at the level of gene-expression-testing the feasibility of a new approach

Differential-display PCR (DD-PCR), a comparative method for detecting alterations in the expression pattern of unknown genes, was applied to identify markers for environmental pollution of the coastal marine environment, in Donax trunculus (Mollusca: Bivalvia). Bivalves collected from a site typified by industrial pollution were compared with bivalves collected from an unpolluted site. Additionally, bivalves from the unpolluted site were exposed in the laboratory to increasing levels of pollution. Multiple responsive fragments, including qualitative and quantitative differentials, were observed in both experimental designs. Fragment-specific primers may be designed for use in diagnostic amplifications, according to the sequence of selected differential fragments. This study is a first step toward the establishment of a marine warning and monitoring system based on the most basic level of biological response.