Microinjection of Cloned DNA Fragments into Fertilized One-Cell Mouse Eggs: I. Manual Injection

Central to the process of making transgenic mice is the physical introduction of cloned DNA fragments into fertilized one-cell mouse eggs. First described 10 years ago by a number of investigators (1 –5 ), microinjection remains the most popular and successful of the methods currently available for generating transgenic animals. Microinjection continues to be the method of choice, because the advantages of speed and reliability far outweigh the demands placed on the investigator for precise technical skill and expensive equipment.