Patent ID: 7682828

Claim:
A primary somatic cell comprising in its genome a first endogenous pluripotency gene operably linked to DNA encoding a first selectable marker in such a manner that expression of the first selectable marker substantially matches expression of the first endogenous pluripotency gene, wherein the cell additionally comprises an exogenously introduced nucleic acid encoding a pluripotency protein and operably linked to at least one regulatory sequence, wherein the endogenous pluripotency gene is a gene that is expressed in a pluripotent embryonic stem cell, is required for the pluripotency of the embryonic stem cell, and is downregulated as the embryonic stem cell differentiates, and wherein the pluripotency protein is a protein expressed in a pluripotent embryonic stem cell, is required for the pluripotency of the embryonic stem cell, and is downregulated as the embryonic stem cell differentiates.