Transgenic Mouse

Definition

A transgenic mouse contains additional, artificially introduced genetic material/DNA in every cell. The foreign DNA that has been purposely inserted into the mouse genome can be a foreign gene (not usually present in mice), a gene from the mouse, or a gene with a mutation (mutation: a change in the DNA code that alters the protein properties). The foreign gene is carefully constructed using recombinant DNA technology. In addition to the target gene itself, the DNA also includes other sequences that ensure:

• Incorporation into the genomic DNA of the mouse

• Proper expression of the gene by the cells

In order to incorporate the foreign DNA into every cell of the mouse, it has to be introduced into very early mouse embryo so that the germ cells (sperm and ovum) also receive the gene and pass it on to the next generation.

Characteristics

Methodology

There are two major methods that can be used to generate a transgenic mouse:

• Pronuclear microinjection: Foreign DNA is introduced...