9th Annual Workshop, October 28-31, 1999
Co-sponsored by the U.S. Department of Energy
Using large cloned genomic fragments as expression vectors to create or correct mutant phenotypes
E. Passage and M. Fontés
INSERM U491, Marseille Cedex 5, France
The development of genomic resources (YAC, BAC, PAC), which have been largely used for gene hunting and systematic sequencing, ask the question of using these clones as expression vectors. These clones will have the following advantages: - One would expect there to be stable expression which would last for the whole of the transfected cell's life - Expression levels are similar to those found for endogenous copies. - The control of transgenic expression should perfectly reproduce that of the endogene. This removes the risk of adverse phenotypic effects resulting from expression of the transgene where it is not normally produced. Another advantage of this approach is that expression is not dependent on the site of integration. - This method does not produce any inflammatory, allergic or immune responses as it has been described in viral based gene therapy approaches.
We have thus developed this approach to create mouse models of human inherited disease, by injection of YAC or PAC in the murine oocyte. Two models will be presented: Charcot-Marie-Tooth disease type 1A (YAC injection) and Creutzfeld-Jacob/Prion Diseases (PAC injection). We may note that this approach can be used to check expression and provide information on the role of genes in a given genomic fragment.
Moreover, we are now developing this technology in a gene therapy approach, using ex vivo or in vivo approaches, the strategy we will used for Polykystic Kidney Disease type 1 gene therapy, will be presented.