Conditional gene knockout
Encyclopedia
Conditional gene knockout is a relatively new technique, an offshoot of gene knockout
Gene knockout
A gene knockout is a genetic technique in which one of an organism's genes is made inoperative . Also known as knockout organisms or simply knockouts, they are used in learning about a gene that has been sequenced, but which has an unknown or incompletely known function...

 technology with the exception that a specific target gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

 is eliminated from a single organ in the body rather than the whole body as gene knockout technology would entail. Thus this allows for more sophisticated experiments than traditional gene knockout studies and hence more useful and practical in its approach. There are several advantages conferred by this technique over the conventional type in that such genetically modified mice are not only able to survive longer but also, the technique overall is more clean and scientifically precise. The most commonly used technique for conditional gene knockout is the Cre-Lox recombination
Cre-Lox recombination
Cre-Lox recombination is a special type of site-specific recombination developed by Dr. Brian Sauer initially for use in activating gene expression in mammalian cell lines and transgenic mice . Subsequently, the laboratory of Dr...

 system. Cre recombinase
Cre recombinase
Cre recombinase, often abbreviated to Cre, is a Type I topoisomerase from P1 bacteriophage that catalyzes site-specific recombination of DNA between loxP sites. The enzyme does not require any energy cofactors and Cre-mediated recombination quickly reaches equilibrium between substrate and reaction...

 is known to be expressed in only a few target cell types and hence the researcher would be typically able to decide where exactly the gene in question is to be knocked out thus allowing for a greater degree of freedom and scientific accuracy.

Latest advances

A team of researchers from UT Southwestern Medical Center have successfully knocked out a specific gene in mouse brain thought to be involved in the onset of Alzheimer's disease
Alzheimer's disease
Alzheimer's disease also known in medical literature as Alzheimer disease is the most common form of dementia. There is no cure for the disease, which worsens as it progresses, and eventually leads to death...

 which codes for the enzyme cyclin-dependent kinase 5
Cyclin-dependent kinase 5
Cell division protein kinase 5 is an enzyme that in humans is encoded by the CDK5 gene. The protein encoded by this gene is part of the cyclin-dependent kinase family.-Physiological Role:...

(Cdk5). Such genetically-engineered mice were found to be 'smarter' than normal mice and were able to handle complex tasks more intelligently compared to 'normal' mice bred in the laboratory.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK