How does the DNA microinjection technique of transgenesis work?

1. collect fertilized oocytes or embryonic stem cells (from fertilized blastocysts). 2. inject the genes of interest in the oocytes or inner cell mass of the stem cells. 3. culture the oocyte into a blastocyst or insert the cells into a blastocyst. 4. perform genetic tests, freeze the cells or transplant them into a recipient.