(2)显微注射法 (microinjection 利用显微操作把目的基因直接注入靶细胞或细胞核 Transgenic Mice Female Male Microinjection Pipette pronucleus pronucleus Holding DNA Solution Pipette Transgene Integration
（2）显微注射法 （microinjection ） 利用显微操作把目的基因直接注入靶细胞或细胞核
例：转基因动物的制备 重组基因DNA 微注射（体外） 小鼠受精卵 回植 假妊娠 仔鼠 动物模型：转基因鼠 (每个鼠细胞中都含有外源基因，按孟德尔方式遗传)
例：转基因动物的制备
Transgenic Mice Female Male Microinjection Pipette pronucleus pronucleus Holding DNA Solution Pipette Transgene Integration in the Genome Transgene Multiple copies integration at a random site in the genome Transfer to pseudopregnant female Transgenic mouse (transgene present in all nucleated cells)