基因打靶研究最重要的应用之一是研制人类疾病动物模型。人类的疾病许多是由于基因功能丧失引起的 ,也有许多是由于基因超表达或功能获取 (ｇａｉｎｏｆｆｕｎｃｔｉｏｎ)引起的。后者的情况就无法用基因剔除的方法获得相应的疾病模型。因此研究者发明了各种可以将诸如插入终止 One of the most important applications of gene targeting research is to develop an animal model of human disease. Many human diseases are caused by the loss of gene function, and many are due to gene over-expression or gainoffunction. The latter case can not use the gene knockout method to obtain the corresponding disease model. So researchers have invented various kinds of terminology such as insertions