Review tackles minimizing variation of transgene expression
CropBiotech Net, September 22, 2005
http://www.isaaa.org/kc/

Although gifted with the promise of rendering a plant immune to disease or insect attack, transgenes can sometimes be unstable and unpredictable. The sources of such variations include inconsistency in the copy numbers of the introduced gene or genes; somaclonal variation, or phenotypic differences amongst the biotech plants created; the site of insertion of the transgene; and RNA silencing in the host plant. As a result, researchers are spending more time and money to both achieve stable transgene expression, as well as to produce biotech crops with the expected level of expression. Katleen M.J. Butaye and colleagues of the Katholieke Universiteit Leuven, Belgium review these techniques in ³Approaches to minimize variation of transgene expression in plants.² The article is published in the latest issue of Molecular Breeding. The review expounds on such techniques as Cre-Lox co-transformation, where the introduced gene is flanked by DNA sequences which will allow the gene to be stably integrated into the host genome. This technique has proven to be successful in mammalian cells, but is still inefficient for plants. Other techniques include the use of new gene cassettes, viral suppressor genes, and, according to the researchers, the ultimate genetic engineering tool: plant artificial chromosomes.
Read the abstract at http://dx.doi.org/10.1007/s11032-005-4929-9.
Subscribers to Molecular Breeding can access the full article through the same page.

Web Link: http://www.isaaa.org/kc/CBTNews/2005_Issues/Sept/
CBT_Sept_16.htm#10