Animal transgenesis

Abstract

Transgenic animals were obtained for the first time 17 years ago. This technique is widely used in basic research. Genes can be added, inactivated or specifically replaced in the genome of animals. This technical approach brings invaluable and numerous informations on the genome working and on the control mechanisms of biological functions. The production of recombinant proteins in the milk of transgenic animals is about to become an industrial activity. The transfer of organs (heart, kidney, lung...) and cells (pancreas, liver...) from transgenic pigs to humans seems no more inaccessible. The use of transgenesis to improve animal production is still almost inexistent. It is restricted essentially to the obtention of models to study particular genes and biological functions. The technical difficulty and the cost to generate transgenic farm animals remain one of the major limitations for the applications in this field. However, gene transfer into cultured fÏtal cells followed by their transfer into enucleated oocytes to generate living animals should greatly contribute to improve this situation. Transgenic farm animals having interesting genetic traits should be obtained in the coming years. However, transgenesis will not be used instead of other methods (selection, vaccination, control of reproduction...) which are also making quite significant progress. Transgenesis is rather an additional technique to improve animal production.