BioCentury
ARTICLE | Company News

University of North Carolina other research news

August 26, 1996 7:00 AM UTC

University researchers published a method to choose exactly where to insert genes among a mouse's genes. This method of targeted transgenesis relies on homologous recombination in embryonic stem (ES) cells of mice, so that the mice bear a single copy of the transgene. Prior approaches ended up with multiple copies of inserted genes that did not always get expressed at appropriate levels due to random placement within the genome. Moreover, the random insertion can disrupt the mouse's own genes.

As reported in the Proceedings of the National Academy of Sciences, a mouse bcl-2 cDNA, driven by either a chicken beta- actin promoter or a human beta-actin promoter, was inserted immediately 5' to the X-linked gene hypoxanthine phosphoribosyltransferase. The level of gene expression was shown to be consistent in all animals bearing the transgene with the same promoter, but differed between the two promoters. In contrast, the expression of bcl-2 transgenes having the same (chicken beta-actin) promoter varied drastically when they were independently integrated at random insertion sites. ...