The figure summarizes the nuclear transfer (NT) process as used to create genetically defined hES cell lines. (1) Hyperovulation of female oocyte donors, surgical harvest of oocytes, and oocyte enucleation via micromanipulation to create an ooplast. (2) Research subject somatic-cell donation and enucleation via micromanipulation to isolate donor nucleus. (3) Microinjection of donor nucleus into ooplast to create a reconstituted oocyte. (4) Activation of reconstituted oocyte to induce mitosis. (5) Isolation of inner-cell mass from blastocysts via immunosurgery and establishment cultivation of hES cell line. (6) In vitro analysis/directed differentiation of hES cells. (7) Cellular therapy with in vitro–differentiated, genetically repaired hES-cell derivatives.