Transgenic mice: A powerful tool for basic research
Our intention with this paper is to explain why transgenic mice have become an indispensable tool to molecular biology. The central parts of the paper are: a description of how transgenic mice are made by microinjection of DNA into the nucleus of an early embryo, a background orientation about molecular biology, and three examples of uses of transgenic mice. The examples illustrate how transgenic mice can be used to help in the answering of the following grand questions: 1. How is an individual gene regulated during the embryological development? 2. How is cell proliferation normally controlled, and how does the control become defective when normal cells turn into cancer cells? 3. How can a gene defect be related to function as seen in the individual and in an affected tissue? Furthermore, we discuss some difficulties that concern the making oftransgenic animals and finally comment briefly on a few further develop— ments, present and immediately foreseen.