Risk assessment of Horizontal Gene Transfer in contaminants bacterias of <em>in vitro</em> cultures sugarcane

Abstract

The horizontal gene transfer is a phenomenon that must be taken into account when performing risk evaluation ofgeneticallymodifiedplants, becausetheseonescouldtransmit bythis methodtheartificially incorporated transgenes to other organisms with those they are in strait contact in the environment and affect them somehow. The aim of this study was to evaluate the risks of horizontal gene transfer in contaminant bacterial species of in vitro non-transgenic sugarcane cultivations (Saccharum spp. hybrid), which in some cases coincide with endophytic species and/or residents of the rhizosphere of transgenic plants. It was determined the capacity of natural transformation of fourteen bacterial strains with a plasmid containing genes that confer resistance to antibiotics Ampicillin, Streptomycin and Spectinomycin, used as a vector for plant genetic transformation, and from the calculationof transformation frequenciesofeach species the risks were assessed. Transformed and non transformed bacterias were obtained, the lowerfrequency was obtained for Escherichia coli (0.09 x 109) and the highest for Pseudomonas stutzeri (266.6 x 109). The fact that some of the studied bacterias were naturally transformable is a risk factor for them, and they can be used as a model to study horizontal gene transfer, in case to be found as endophytic or associated with the rhizosphere of plants that have been genetically modified when conducting risks assessments to such plants. Key words: Risks evaluation, Horizontal Gene Transfer