Conclusión
La transferencia horizontal de genes es un fenómeno comprobado. Esto ha ocurrido en nuestro pasado evolutivo y continúa hoy en día. Todos los signos indican que la transferencia horizontal de genes en un proceso regulado, limitado por las barreras existentes entre las especies y por mecanismos que se deterioran e inactivan por la presencia de material genético extraño. Lamentablemente, la ingeniería genética ha creado una enorme variedad de construcciones artificiales diseñadas para cruzar las barreras entre las especies e invadir todos los genomas. Aunque las construcciones básicas sean las mismas para todas las aplicaciones, algunas de las más peligrosas pueden proceder de la eliminación de los desechos confinados en los organismos transgénicos (50). Esto incluye construcciones que contienen genes del cáncer y de células utilizadas en las investigaciones de laboratorios de medicinas contra el cáncer, y que se encuentran en la fase de desarrollo, bacterias con genes de gran virulencia y virus de laboratorios de patologías. Resumiendo, la biosfera está siendo expuesta a todas clase de nuevas construcciones y combinaciones de genes que no han existido antes en la naturaleza, y que nunca podrían haberlo hecho, gracias a la labor de la Ingeniería Genética.
Hay una necesidad urgente de establecer un regular eficaz, en primera instancia, que prevenga de fugas y liberaciones de estas peligrosas construcciones al ambiente, y considerar luego si estos experimentos no debieran de estar permitidos en absoluto.
Referencias
1.Thanks to Dr. Beatrix Tappeser, Institute for Applied Ecology, Postfach 6226, D-79038, Freiburg, forthis information. See also Barnett, A. (2000). GM genes ‘jump species barrier’ The Observer, May 28,2000.2.See Stephenson, J.R., and Warnes, A. (1996). Release of genetically-modified miroorganisms into theenvironment. J. Chem. Tech. Biotech. 65, 5-16; Harding, K. (1996). The potential for horizontal genetransfer within the environment. Agro-Food-Industry Hi-Tech July/August, 31-35; Ho, M.W. (1996). Arecurrent transgenic technologies safe? In Virgin, I. and Frederick R.J., eds. Biosafety Capacity Building,pp. 75-80, Stockholm Environment Institute, Stockholm; Traavik, T. (1999). Too Early May be TooLate, Report for the Directorate for Nature Research, Trondheim, Norway.3.See http://www.i-sis.org4.See Ho, M.W. (1998, 1999). Genetic Engineering Dream or Nightmare? The Brave New World of BadScience and Big Business. Gateway, Gill & Macmillan, Dublin; Ho, M.W., Traavik, T., Olsvik, R.,Tappeser, B., Howard, V., von Weizsacker, C. and McGavin, G. (1998). Gene Technology and GeneEcology of Infectious Diseases. Microbial Ecology in Health and Disease 10, 33-59.5.See Ho et al, 1998 (note 4) and references therein.6.See Lorenz, M.G. and Wackernagel, W. (1994). Bacterial gene transfer by natural genetic transformationin the environment. Microbiol. Rev. 58, 563-602.7.See Ho,1998, 1999 (note 4; Ho, et al, 1998 (note 4).8.See Ho, M.W., Ryan, A., Cummins, J. and Traavik, T. (2000a). Unregulated Hazards: ‘Naked’ and‘Free’ Nucleic Acids, ISIS & TWN Report, London and Penang. http://www.i-sis.org.9.Grillot-Courvalin, C., Goussand, S., Huetz, F., Ojcius, D.M. and Courvalin, P. (1998). Functional genetransfer from intracellular bacteria to mammalian cells. Nature Biotechnology 16, 862-866.10.See Nielsen, K.M., Bones, A.M., Smalla, K. and van Elsas, J.D. (1998). 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* Mae-Wan Ho, Institute of Science in Society and Department of Biological Sciences,Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
