Transgenic mice. Drought-tolerant canola. Medication-producing plants. And the still-unrealized potential of gene therapy. These four represent just a small sampling of the power of gene-targeting technology. But as researchers are painfully aware, gene targeting could be more powerful still. The problem, explains Michael Fernandez, director of science at the Pew Initiative on Food and Biotechnology, "is that whenever genes go into plants [or animals], they may inadvertently alter another function." This is possible largely because of the randomness of gene insertion: An inserted gene may end up anywhere in the genome. As a result, the relocated gene may not be expressed in the desired way or even at all. "Gene transfer normally is random," says Tom Hodges, J.C. Arthur distinguished professor emeritus, Purdue University. "Sometimes genes are expressed well, sometimes not, and they aren't always passed to the next generation properly."
The goal, therefore, is to insert the gene into ...
