Oncogene Transfer into the Brain

With the spectacular advances in the characterization of genes associated with brain tumors and other neurological disorders, experimental approaches to stably introduce and express foreign genes in vivo have recently evolved as an important tool to study the specific pathogenetic role of candidate genes. A well-characterized and frequently used model are transgenic mice (Wagner 1990; Hanahan 1989; Pattengale et al. 1989). These animals are generated by introduction of DNA constructs into fertilized eggs or into embryonic stem cells. They carry copies of the transgene in all somatic and germ cells and stably transmit the gene to their offspring in a Mendelian fashion. Transcription of the transgene is critically dependent on regulatory sequences. Using specific promoter elements, it is possible to achieve cell- and tissue-specific expression. Cross-breeding of transgenic lines which carry distinct transgenes allows to study the combined effects of the respective genes in vivo.