Production of transgenic and mutant mouse models.

Manipulation of the rodent genome by deliberately inserting (transgenic) or removing (knockout) a gene of interest or indeed by selectively breeding animals with a spontaneous or random mutation producing a trait of interest has been developed over several years. Mouse "fanciers" have been selectively breeding interesting mice since the turn of the last century to produce a plethora of different background strains of the common house mouse (Mus musculus). Rat (Rattus norvegicus) strain development has also proceeded with selective breeding, although the range of strains is more limited. The deliberate and targeted manipulation of the mouse genome has been with us for over two decades, with the rat genome a more recent addition, and yet this technology has been limited to a very narrow range of genes. With the complete mapping of the mouse genome (and the rat genome soon to follow), the powerful techniques of transgenic and knockout rodent production can be applied to the numerous genes whose expression is altered in existing stroke models.