Animal Biotechnology and Modeling
Transgene-encoded mRNA Expression
Conclusions and Future Directions
Gene Transfer Today
Books and Reviews
A gene-transfer technique utilizing micromanipulation to inject DNA constructs
(transgenes) directly into the pronuclei or nuclei of cells. The foreign DNA integrates
into the host cell genome at a random location and usually in concatemers. DNA
microinjection is the most commonly used gene-transfer technique for creating
transgenic mammalian species.
Embryonic Stem (ES) Cell Transfer
The transfer of genetically manipulable pluripotent embryonic stem cells into a
developing embryo; achieved by microinjection of stem cells into blastocysts or
coculture with earlier stage ova. The resultant transgenic animal possesses a
proportion of cells descended from the embryonic stem ES-cell lineage. Gene targeting
resulting in both loss-of-function (knockout) and gain-of-function (knockin) is possible.
In mammalian species, this gene-transfer technique has been successful only in
producing germ line transmission of ES cell lineages in mice.
A set of techniques directed toward manipulating biological function via the
introduction of foreign DNA sequences (genes) into living cells.
The nucleus of a cell with organism-speci±c DNA is provided by a donor cell and
introduced into an enucleated oocyte (unfertilized ovum) or zygote, allowing for
reprogramming fate of the developing embryo.
An animal either integrating foreign DNA segments into its genome following gene
transfer, or resulting from the molecular manipulation of endogenous genomic DNA.