Homologous Recombination in Mammalian Somatic Cells

Abstract

During the last decade, gene-transfer methods using purified DNA have developed from a novelty to a powerful tool in the study of gene structure-function relationships. Though success with DNA transfer was reported as early as 1962 (Szybalska and Szybalski, 1962), widespread use of this method had to await later developments. On the basis of a method developed by Graham and van der Eb (1973), Wigler et al. (1977) and Maitland and McDougall (1977) successfully introduced the herpes simplex virus (HSV) thymidine kinase (TK) gene into mouse cells deficient in this enzyme. Wigler and colleagues were also able to identify and isolate from the HSV genome a fragment of DNA that carried the TK gene. The calcium phosphate coprecipitation method was augmented by other methods of gene transfer such as DEAE-dextran-mediated transfer (McCutchan and Pagano, 1968; Sussman and Milman, 1984; and Milman and Herzberg, 1981) microinjection into somatic cells (Anderson et al., 1980; Capecchi, 1980) or into embryos (Gordon et al., 1980). Understanding the structure of DNA and RNA viral genomes has permitted the construction of a variety of different vectors for introduction of genetic information into mammalian cells (see Chapters 5 and 6). The availability of these different methods for gene transfer makes it possible to introduce virtually any gene into mammalian cells.