J Physiol Volume 582, Number 2, 481-488, July 15, 2007 DOI: 10.1113/jphysiol.2007.134908
Genetically manipulated mice: a powerful tool with unsuspected caveats
Klaus I. Matthaei1
1 Gene Targeting Laboratory, The John Curtin School of Medical Research, Building 131, Garran Road, The Australian National University, Canberra, ACT 0200, Australia
Although genetic manipulations in mice have provided a powerful tool for investigating gene function in vivo, recent studies have uncovered a number of developmental phenomena that complicate the attribution of phenotype to the specific genetic change. A more realistic approach has been to modulate gene expression and function in a temporal and tissue-specific manner. The most common of these methods, the CreLoxP and tetracycline response systems, are surveyed here and their recently identified shortcomings discussed, along with a less well known system based on the E. coli lac operon and modified for use in mammals. The potential for further complications in interpretation due to hitherto unexpected epigenetic effects involving transfer of RNA or protein in oocytes or sperm is also explored. Given these problems we reiterate the necessity for the use of completely reversible methods that will allow each experimental group of animals to act as their own control. Using these methods with a number of specific modifications to eliminate non-specific effects from random insertion sites and inducer molecules, the full potential of genetic manipulation studies should be realized.
(Received 18 April 2007;
accepted after revision 10 May 2007;
first published online 10 May 2007)
Corresponding author K. I. Matthaei: Gene Targeting Laboratory, The John Curtin School of Medical Research, GPO Box 334, Canberra City, ACT 0200, Australia. Email: klaus.matthaei{at}anu.edu.au
Copyright © 2007 The Physiological Society.
