Alteration of gene expression in muscle tissue and mammary gland from recombinant somatotropin treated animals: searching for biomarkers

rbST is a peptide hormone banned within the European Union (Council Decision 1999/897/CE). Direct approaches aimed at identifying rbST-treated dairy cattle often produce controversial results. The reason can be found in the difficulty in distinguishing the synthetic molecule from the natural one due to their extreme similarity. However, the use of particular monoclonal antibodies with a higher affinity for the recombinant forms (Castigliego et al. 2006) or the employment of immunochemical techniques associated with bidimensional electrophoresis (Iannone et al. 2005) have been proposed as ways to facilitate the recognition of treated animals. Other experimental approaches are based on the research into biological markers capable of revealing possible treatments, according to physiological changes caused by the action of the exogenous hormone. In this work we have compared the expression of a number of genes belonging to the somatotropic axis, in the muscles and in the mammary gland of rbST-treated cows and controls, in order to highlight differences to be potentially employed for investigations in the field of food inspection.