The use of genetic recombination technology to alter genetic sequences in embryonic stem cells is known as gene targeting. After a scientist modifies the genome, the cells can be injected into a developing embryo in a procedure known as embryonic injection. The embryo will be a chimera, made up of a mix of altered and normal cells. The scientist can create animals that express or don’t express the desired gene using embryos with the target genes in their reproductive cells.
The identification of a specific gene is the first step in gene targeting. This necessitates the use of gene sequencing technology as well as theories about which regions of the genome contain coding DNA with active genes and what those genes do. The scientist can create a new strand of DNA that is carried by a vector and latches onto the desired section of the genome. This entails the use of sophisticated scientific equipment in a controlled setting.
The new strand of DNA may be able to silence a gene, which is the first step toward knocking out a gene. Because mice are popular for research, this is most commonly used in them, and an engineered mouse of this type is known as a “knock-out mouse.” The organism will not express the given gene, which could lead to the development of a genetic disorder or a change in the animal’s physical appearance. This information can aid researchers in determining which genes are involved in genetic disorders and determining what each gene does.
It’s also possible to make a knock-in organism, in which the gene that’s being targeted inserts new DNA. The DNA will express itself and may alter the physical characteristics of the animal. In both cases, a tag is usually inserted to allow the researcher to determine whether or not the gene targeting was successful. If a scientist wants to know if inserted DNA is present in a cell, they can use DNA sequencing technology to look for it. This is critical for procedures in which researchers want to make sure they’re working with an organism that has the DNA they’re looking for.
Researchers can use gene targeting for a variety of purposes. These can include disease and congenital disorders research, as well as experiments to test the efficacy of gene therapy. Scientists can insert DNA into mature organisms to change the way their genomes express in gene therapy. This technology could be used to treat a variety of conditions, such as enzyme deficiencies, by instructing the body to begin coding for the missing enzyme.