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3rd South-European Bioethic Forum Mali Lošinj, 20-22 September 2007 Scientific and bioethic complaints against the genetic enginering Marijan Jošt Agricultural College Križevci Abstract It is clear today that the general public opinion is against the genetic engineering (GE) on plants and animals as well as genetically modifyed ingredients in food. Sadly, the main support for GE comes from some educated academic people; even when their profession is far from molecular biology and genetics, their belief in science is so firm that they rule out any logical criticism and proclaim it as non-scientific. The mistakes of GE and the wrong scientific approach of molecular biologists are presented from the viewpoint of a plant breeder. Besides the scientific mistakes on which the GE is based, bioethic reasons against the acceptance of genetically modified organisms (GMO) is explained according to the Lošinj declaration. And last but not least, the economic and political background of genetic engineering will be elucidated. Key words: genetic engineering, science, bioethics, politics. Introduction To folow scientific and bioethic complainst against genetic engineering, we should first explain what is genetic engineering. Just look at one of several definitions: Genetic engineering is a set of biotechnological methods used to transfer foreign DNA segment through biological barriers of different species. This event - transfer foreign DNA segment through biological barriers of different species is also knovn as ‘Horizontal gene transfer‘. Why horizontal? In nature, a common transfers of genes is from parents to ofspring, and this is called 'vertical gene transfer'. Quite oposite is in case of gene transfer between different, nonrelated species vhich is not hapeninh in nature over a short period of time. Jes, here time is important, because even this 'horizontal' gene transfer could occours during extremeli long period of time. For instance: throughout milenies of human being evolution some foriegn genes vere incorporated in human body. So, today for instance, it is known that 113 genes have been transferred into the human genome from bacteria. Examples of crossings: The same species (subspecies): diferent cultivars of wheat or breeds of dogs Closely related species: donkey x horse = mule Different species or families: tomato x fish YES Sometimes Sterile ofspring NO To obtain unnatural and upossible 'horizontal' gene transfer between diferent unrelated species scientist are using special techniks: Agrobacterium mediated transformation – the easiest and most simple plant transformation, but many plants are not transformable by this method and it is not used in GE now. Particle bombardment: Coat small gold or tungsten particles with DNA and shoot them into young plant cells or plant embryos. Some genetic material will stay in the cells and transform them. This method also allows transformation of plant plastids. The transformation efficiency is lower which incloode an artificial DNA construction caled vector. Vector is a modified pathogen virus or bacterium, used to perform transfer of the gene construction. Besides DNA segment which is known to code certain desirable characteristics and which should be transfered, in vector are incorporated also: Promoter is from Cauliflower mosaic virus (CaMV 35S). The promoter (CaMV 35S) of the 35S RNA is very strong, and well known for its use in plant transformation. Its duty is to start action of the inserted gene. Marker (ABR gene) is used to prove successful transfer of DNA construction into the tissue culture from which a new GMO will be developed. Promoter (CaMV 35S) Inserted gene for desired trait Marker (ABR gene) Plants A number of mechanisms are available to transfer DNA into plant cells: Agrobacterium mediated transformation is the easiest and most simple plant transformation. Plant tissue (often leaves) is cut into small pieces, eg. 10x10mm, and soaked for 10 minutes in a fluid containing suspended Agrobacterium. Some cells along the cut will be transformed by the bacterium, that inserts its DNA into the cell. Placed on selectable rooting and shooting media, the plants will regrow. Some plants species can be transformed just by dipping the flowers into suspension of Agrobacterium and then planting the seeds in a selective medium. Unfortunately, many plants are not transformable by this method. Particle bombardment: Coat small gold or tungsten particles with DNA and shoot them into young plant cells or plant embryos. Some genetic material will stay in the cells and transform them. This method also allows transformation of plant plastids. The transformation efficiency is lower than in agrrivatedbacterial mediated transformation, but most plants can be transformed with this method. Electroporation: make transient holes in cell membranes using electric shock; this allows DNA to enter as described above for Bacteria. Viral transformation (transduction): Package the desired genetic material into a suitable plant virus and allow this modified virus to infect the plant. If the genetic material is DNA, it can recombine with the chromosomes to produce transformant cells. However genomes of most plant viruses consist of single stranded RNA which replicates in the cytoplasm of infected cell. For such genomes this method is a form of transfection and not a real transformation, since the inserted genes never reach the nucleus of the cell and do not integrate into the host genome. The progeny of the infected plants is virus free and also free of the inserted gene. [edit] Animals Introduction of DNA into animal cells is usually called transfection, and is discussed in the corresponding article. [edit] References 1. ^ Chen I, Dubnau D (2004). "DNA uptake during bacterial transformation". Nat. Rev. Microbiol. 2 (3): 241–9. doi:10.1038/nrmicro844. PMID 15083159.^ Largevolume transformation with high-throughput efficiency chemically competent cells. Focus 20:2 (1998). 3. ^ Transformation efficiency of E. coli electroporated with large plasmid DNA. Focus 20:3 (1998). 1. Scientific arguments against GE The mistakes of GE and the wrong scientific approach 2. Bioethic arguments against GE Bioethic reasons against the acceptance of genetically modified organisms 3. Economic and political background of genetic engineering References Pelanda C. Global Ecopolicy - Preliminary Paper. GLOBIS, University of Georgia, Athens, GA, USA <http://www.carlopelanda.com/italian/ricerca/Gloecopolicyjan02.htm> Marijan Jošt Agricultural College Križevci M. Demerca 1 48260 Križevci E-mail: [email protected]