3. Genetic engineering is the process of transferring specific
genes, from the chromosomes of other organisms in such a
way that they become the reproductive part of the new
organisms. The process that produce recombinant.
Recombinant DNA technology is the field of molecular
biology which refers to joining DNA from two different
species and inserting it into specific host which allows the
recombinant DNA to express and produce new synthetic
molecular that are of value for medicine, industry and
agriculture.
4. Recombinant DNA technology is used for obtaining one of
the following objectives:
1. To produce large quantity of product from gene of
interest.
2. To synthesize many identical copies of specific of
specific gene or DNA fragment that is called gene
cloning.
3. To insert gene of interest into chromosomes of target
organism so that the gene expresses there and produce
the encoded product.
5. The basic steps involved in the genetic engineering are as
follows:
Isolation of gene or fragment of interest which is to be cloned
or encodes the product desired to be synthesized by cutting it
with specific restriction enzymes.
Insertion or recombination of desired gene into specific
vector like plasmids, yeast artificial chromosomes etc with the
help of DNA ligase.
Introduction of this recombined vector into suitable cell or
organism known as host (transformation)
Selection of transformed host cells which receives the
recombined DNA.
Multiplication and expression of desired gene in the host.
6.
7. Genetic engineering has application in medicine, research,
industry and agriculture.
It can also be used on a wide range of plants, animals and
microorganisms.
8. Genetic engineering has resulted in a series of medicine. The
1st two commercially prepared products from recombinant
DNA technology were insulin and growth hormones both
were altered E.coli bacteria.
Humulin: It is a form of insulin produced by
genetic engineering of ‘insulin gene’ into E.coli, first marked
by Eli-lillyin 1982.
Humulin structure is similar to human insulin
but its α and β chains are synthesized separately in different
strains of E.coli.
9. TNF: Tumor necrosis factor is also produced by genetic
engineering to treat certain tumor cells.
Interleukin-2: It activates immune system,used in treating
cancer with immune disorder.
Human growth hormone: A human growth
hormone(protropin)is also produced genetic engineering
which is used to treat pituitary diwarfism.
Interferon: It is used in leukemia and is now produced by
DNA recombinant technology using E.coli as host.
10. Anti hemophilic factor: Factor 8 whose deficiency causes
hemophilia A is now available for use in patient with hemophilia by
using this technology.
tpA protein: A thrombolytic agent called tissue plasminogen
activator is prepared for use as drug to dissolve blood clot which are
the cause of heart attack and strokes.
Erythropoietin: It is glycoprotein hormone that plays role in
erythropoiesis and RBC production so recombinant erythropoietin
is used to treat anemia.
β- Endorphin : It is a natural opiate used for pain relief is also
prepared genetically.
11. Vaccines: Genetically engineered vaccines for many
infectious disease. Most common is recombinant Hepatitis-B
vaccine which contains a surface protein from the hepatitis
virus.
This protein is synthesized by recombinant yeast cells and
then purified for injection. The HBV vaccine is much safer to
use than a weakened form of actual virus which of it reverts
back to its original form, could cause liver cancer or hepatitis.
12. Gene therapy is the use of DNA as a pharmaceutical agent
to treat disease.
It drives its name from that idea that DNA can be used to
supplement or alter genes within an individual’s cells as a
therapy to treat disease.
The most common form of gene therapy involves using
DNA that encodes a functional, therapeutic gene to replace
a mutated gene.
13. Gene technology can be used in agriculture and food
production to
Increase crop or animal resistance to pest while
reducing the use of chemicals
Increase crop or animal tolerance to chemicals that are
used to kill harmfull pests
Create disease resistance in crop and animals
Improve the food yield per plant or animal
14. Make plants and animals more suited to environmental
conditions e.g salty water
Improve the nutritional quality of the food produced by
the plant and animals.
15. Recombinant DNA has been used in the development of the
most common diagnostic techniques for HIV.
The antibody test uses a recombinant HIV protein to
measure antibodies in the body that proliferate when
there is a HIV infection.
The DNA test uses reverse transcription polymerase
chain reaction (RT-PCR) to detect presence of HIV
genetic material. This technique was developed using
recombinant DNA of molecules and analyzing the
genome sequences.
15
16. Bacteria produced Bovine growth hormone for increase in
milk production in Cow. Recombinant renin used for
manufacturing cheese now these days instead of
slaugthering calf’s for renin production as was done in old
days.
17. Gene probes are used for diagnostic purpose of genetic
disorders and infectious agents like HIV.
18. This knowledge will provide new understanding of how
gene work,how they are regulated and why they create
biological molecules.
The human genome can then be compared to other known
molecules.
The human genome can then be compared to other
animals and notice the differences.
For example : Shark can never have cancer. There is a
cancer inhibiting gene in shark that can be incorporated
into human with no side effects.
