What are gene targeted mice?
Gene targeting methods are established for several model organisms and may vary depending on the species used. To target genes in mice, the DNA is inserted into mouse embryonic stem cells in culture. Cells with the insertion can contribute to a mouse’s tissue via embryo injection.
Where do transgenic mice carry a foreign gene?
Transgenic animals are animals (most commonly mice) that have had a foreign gene deliberately inserted into their genome. Such animals are most commonly created by the microinjection of DNA into the pronuclei of a fertilised egg which is subsequently implanted into the oviduct of a pseudopregnant surrogate mother.
What is loxP site?
LoxP sites are directional 34 bp sequences made up of two 13 bp recognition sites separated by an 8 bp spacer region. The sequences don’t occur naturally in any known genomes other than the P1 bacteriophage, and are long enough that they are unlikely to occur by chance.
How do you target specific genes?
Potential modifications include deletion, insertion or replacement of endogenous sequence with alternative sequences. Targeting can be achieved by homologous recombination in some organisms (notably, mice), or with site-directed genome editing nucleases.
Is gene targeting the same as gene therapy?
Gene targeting is the use of homologous recombination to make defined alterations to the genome. One of the possible outcomes of gene targeting is the accurate correction of genetic defects, and this would make it the ideal method of gene therapy for single gene disorders.
Where are LoxP sites located?
cis
2.4. LoxP sites can be located in cis surrounding a specific gene, or can be located in trans, where the two LoxP sites are located in separate areas of the genome. One of the advantages of using the Cre–LoxP system is the ability to manipulate the transgene in vivo.
How transgenic mice are produced?
Typically, transgenic mice are generated by microinjecting the transgenic construct into a fertilized egg (oocyte or zygote). Another method to generate transgenic mice is to transfect a transgenic construct into mouse embryonic stem (ES) cells and then inject these cells into mouse blastocysts.
Which is the first method used to produce the transgenic mice?
The first method involves DNA delivery by retroviral infection of mouse embryos at different developing stages.
Where are loxP sites located?