61.   Now, however, hit-and-miss genetic engineering must be used to insert human genes into a pig cell.

62.   One strategy is to insert this gene into cold viruses.

63.   Rabbit embryos have the human gene inserted immediately after fertilization, meaning they do not have to have repeated injections of the gene, Van Willingen added.

64.   Scientists have been inserting genes into crop plants to help them resist insects and herbicides, for example.

65.   Scientists currently insert genes into fertilized eggs in a laboratory, which is a very inefficient way to produce animals that use the genes properly.

66.   Scientists inserted the gene to make GAD into tobacco and potato plants, so that the plants would make lots of GAD.

67.   The advance will also provide a much more efficient way to insert genes into livestock, Wilmut and others said.

68.   The procedure involves inserting genes that stimulate the immune system into cancer cells taken from patients.

69.   The scientists first stripped the virus of any genes that would cause disease, then inserted the gene for the growth factor.

70.   The two scientists studied how tumors developed in plants and they succeeded in inserting genes to produce plants that are resistant to insects or herbicides.