genetic engineering

Genetic engineering:
Genetic engineering, also known as recombinant DNA technology, means altering the genes in a living organism to produce a Genetically Modified Organism (GMO) with a new genotype.
Various kinds of genetic modification are possible: inserting a foreign gene from one species into another, forming a transgenic organism; altering an existing gene so that its product is changed; or changing gene expression so that it is translated more often or not at all.

Basic steps in genetic engineering:
1. Isolate the geneI. General outline of genetic engineering
A. DNA cleavage
B. Production of recombinant DNA
C. Cloning of the recombinant DNA
D. Screening clones

DNA cleavage and Production of Recombinant DNA


• making recombinant DNA
1. restriction enzymes are used to cut up DNA of interest and a “vector” into which you want to place the DNA, making restriction fragments
2. particularly when sticky ends are involved, the target DNA restriction fragment can form base pairs with the vector
3. DNA ligase is then used to join the DNA strand backbones
4. and gel electrophoresis to separate them out according to length. Polymerase chain reaction (PCR) can also be used to amplify up a gene segment, which can then be isolated through gel electrophoresis.[5

Restriction enzymes (RE) are endonucleases that will recognize specific nucleotide sequences in the DNA and break the DNA chain at those points. A variety of RE have been isolated and are commercially available. Most cut at specific palindromic sites in the DNA (sequence that is the same on both antiparallel DNA strands). These cuts can be a staggered which generate “sticky or overhanging ends” or a blunt

2. Insert it in a host using a vector
3. Produce as many copies of the host as possible
4. Separate and purify the product of the gene