Transfection of Gametes: A Method to Generate Transgenic Animals Transfección de Gametos: Un Método para Generar Animales Transgénicos

Transfection methods. The first transfection procedures occurred in the early 1960s and experiments with different cell types and tissues has now become widespread (Wolff & Lederberg, 1994). Different transfection methods have been employed (Mulligan, 1993): a) The in vitro procedure when foreign genes are introduced into cultured cells or tissues. b) The in vivo method, when genes are directly introduced into the tissue (by injection, aerosol, etc); c) The ex-vivo system, in which cells are transfected in vitro and then introduced into a living organism; b and c) Have been the basis for human gene therapies (Anderson, 1998).