Wall R J, Hawk H W, Nel N
Gene Evaluation and Mapping Laboratory, Agricultural Research Service, U.S.D.A., Beltsville, Maryland 20705.
J Cell Biochem. 1992 Jun;49(2):113-20. doi: 10.1002/jcb.240490203.
The feasibility of introducing foreign genes into the genomes of cattle, goats, pigs, and sheep has only recently been demonstrated. Studies have thus far focused on improving growth efficiency or directing expression of pharmaceutical proteins to the mammary glands of these species. The general strategy for producing transgenic livestock and mice is similar. In addition to the obvious difference in scale between mice and livestock experiments, there are noteworthy obstacles that significantly reduce the efficiency of producing transgenic livestock. Low embryo viability, low transgene integration rates, and high animal costs contribute to project costs that can easily exceed hundreds of thousands of dollars. A better understanding of the mechanisms that govern transgene integration should lead to improved efficiencies. But, the full potential of the transgenic livestock system will not be fully realized until: 1) gene constructs can be designed that function in a reproducible, predictable manner; and 2) the genetic control of physiological processes are more clearly elucidated. Newly emerging approaches may resolve at least some of these issues within the next decade.
将外源基因导入牛、山羊、猪和绵羊基因组的可行性直到最近才得到证实。迄今为止，研究主要集中在提高生长效率或将药用蛋白质的表达导向这些物种的乳腺。生产转基因家畜和小鼠的总体策略是相似的。除了小鼠和家畜实验在规模上的明显差异外，还有一些值得注意的障碍显著降低了转基因家畜的生产效率。胚胎活力低、转基因整合率低以及动物成本高导致项目成本很容易超过数十万美元。更好地理解转基因整合的机制应该会提高效率。但是，直到以下情况出现，转基因家畜系统的全部潜力才会得到充分实现：1）能够设计出以可重复、可预测方式发挥作用的基因构建体；2）生理过程的遗传控制得到更清晰的阐明。新出现的方法可能会在未来十年内至少解决其中一些问题。
