Generally detected genes in comparative transcriptomics in bivalves: toward the identification of molecular markers of cellular stress response.

The specificity and representativeness of protein-coding genes identified by transcriptomics as biomarkers for environmental toxicological stress is crucial. We extracted the differential gene expression profile data from 49 published comparative transcriptomic studies of bivalves from January 2004 till November 2014 performed in 15 different bivalve species. Among the studies, 77 protein-coding genes were frequently detected when we use threefold of the average detection frequency as cut-off. Cellular organization and communication, protein and energy metabolism, stress response are the main functional classes of these proteins. We consider if these protein-coding genes represent common cellular stress responses of bivalves.