Project Leader:   
Elizabeth Simpson

Involved Institution:   
Centre for Molecular Medicine and Therapeutics

Technology Application:   
Gene therapy of brain disorders

Research Funding Program:   
Competition III

GE³LS Activity:   
Communicating Controversial Science

Gene therapy delivers healthy genes to replace dysfunctional ones and has been tried worldwide with some tantalizing successes as well as disappointing failures in some human trials. This project will use the latest scientific techniques to help improve the safety of gene therapy. Using bioinformatics, the project will characterize genes expressed in the mouse brain, identifying the particular cells and regions of expression and then determining the regulatory regions in the DNA. The end goal is to generate 160 fully characterized human DNA promoters to drive DNA expression in defined brain regions of therapeutic interest for diseases such as Alzheimer’s, Parkinson’s, and Multiple Sclerosis.

Gene therapy holds a great deal of promise for medical therapeutic intervention. The initial gene therapy trials have shown researchers areas where safety concerns need to be considered. More basic research is needed to fully understand the biology of the disease prior to further clinical investigation. Genes should be targeted to the disease and delivered to specific cell types to reduce side effects caused by altering the functions of healthy cells. Finally, genes should not be inserted randomly into the genome because that can be mutagenic but genes should be delivered to a specific location in the human genome.

As stated above, promoters (gene regulators) should specifically decrease inappropriate expression and this project will characterize human promoters , identifying the ones that drive expression in defined regions of the brain.

As part of a previous project, A Quantitative and Comprehensive Atlas of Gene Expression in Mouse Development, seventeen brain regions of therapeutic interest were isolated from mouse by laser capture microscopy and libraries were prepared with a combination of SAGE-Lite and LongSAGE technologies. Using these data and the genomic expression resources publicly available, genes with medium- to high-level, region-specific expression will be identified.

Fifty genes and their endogenous regulatory regions will be used to generate transgenic mice by homologous recombination and the mouse brains will be tested for region-specific expression of a reporter gene. Once tested, 5’ RACE and bioinformatics tools will analyze the promoter regions and identify the regulatory elements. For each gene, 4 MiniPromoter constructs will be generated by PCR and cloned into a gene-targeting vector to make new transgenic mice. Detailed histological analyses will document the region and cell-type specificity of these MiniPromoters, thus creating a valuable resource for both basic and therapeutic research.