Methods
There are two basic technical approaches to produce genetically modified mice. The first involves pronuclear injection into a single cell of the mouse embryo, where it will randomly integrate into the mouse genome. This method creates a transgenic mouse and is used to insert new genetic information into the mouse genome or to over-express endogenous genes. The second approach involves modifying embryonic stem cells with a DNA construct containing DNA sequences homologous to the target gene. Embyonic stem cells that recombine with the genomic DNA are selected for and they are then injected into the mice blastocysts. This method is used to manipulate a single gene, in most cases "knocking out" the target gene, although more subtle genetic manipulation can occur (e.g. only changing single nucleotides).
Read more about this topic: Genetically Modified Mouse
Famous quotes containing the word methods:
“Cold and hunger seem more friendly to my nature than those methods which men have adopted and advise to ward them off.”
—Henry David Thoreau (1817–1862)
“How can you tell if you discipline effectively? Ask yourself if your disciplinary methods generally produce lasting results in a manner you find acceptable. Whether your philosophy is democratic or autocratic, whatever techniques you use—reasoning, a “star” chart, time-outs, or spanking—if it doesn’t work, it’s not effective.”
—Stanley Turecki (20th century)
“A writer who writes, “I am alone” ... can be considered rather comical. It is comical for a man to recognize his solitude by addressing a reader and by using methods that prevent the individual from being alone. The word alone is just as general as the word bread. To pronounce it is to summon to oneself the presence of everything the word excludes.”
—Maurice Blanchot (b. 1907)