[Toxicogenomics. New perspectives for the molecular toxicology]

Gene expression in the cellular genome is subject to changes caused by internal and external factors. Due to different expression of gene sets (polymorphism), cells show different morphological and functional characteristics. Environmental and occupational toxic agents may influence cells at the level of transcription and translation. The functional toxicogenomics attempts to explain those influences. Due to recent developments in molecular biology and bioinformatics, it has become possible to analyze protein transcript (toxicogenomics) and profile (toxicoproteomics). This work reports new opportunities to study gene sequencing and expression by means of the DNA chip technique (rapid analysis of the genetic polymorphism) and the microarrays technique (simultaneous analysis of hundreds or thousands of genes). The authors report examples of some practical applications of toxicogenomics in the assessment of the effects of pathological exposures to environmental and occupational toxic (carcinogenic, hepatotoxic and/or neurotoxic) agents, due to the development of new groups of biomarkers, such as biomarkers of individual susceptibility, biomarkers of toxic effects combined with the assay of the relationship between a toxic agent and its dose, and the effect measured at the level of the cellular genome and results of histopathological and biochemical tests.