At present transgenic lines can be routinely produced from a large number of major crop species. Some of these are now being introduced, or will shortly be introduced into practice in many countries. Consequently, variability in the expression of the inserted transgenes or the possibility of their inactivation has been one of the major challenges facing molecular biologists in recent years. The occurrence in the genome of several copies of transgenic sequences exhibiting complete or partial homology often leads to a reduction in the level of transgenic expression or to gene inactivation. The phenomenon of transinactivation, previously thought to be caused by a single factor, now appears to be the result of a complex process. At the same time this phenomenon opens up possibilities that could be of practical interest, for instance in the development of virus-resistant transgenic plants. The aim of the review is to give a concise description of the factors and processes involved in gene inactivation and of the experimental approaches employed to moderate the reduction in gene expression due to transinactivation.
|Number of pages||9|
|Publication status||Published - Aug 1 1997|
ASJC Scopus subject areas
- Agronomy and Crop Science