The document discusses the application of rDNA technology and genetic engineering in medicine, emphasizing its use in producing vaccines, hormones like insulin, lymphokines, somatostatin, blood clotting factors, and cancer treatment. It highlights the safety of gene-cloned vaccines, the FDA approval of recombinant insulin in 1982, and the role of monoclonal antibodies in targeted cancer therapy. Overall, genetic engineering has transformed medical approaches, enabling safe and effective production of essential biological agents.

1. Application of rDNA
Technology and Genetic
Engineering in Medicine

2. 1. Vaccines
 rDNA technology is used for producing vaccines against disease by
isolating antigen or protein present on the surface of viral particles.
 Vaccines containing a form of an infectious organism that does not cause
but allow the body immune system to form antibodies against the infective
organism.
 When an individual receives vaccination against any viral disease, the
antigens produce antibodies to act against and inactivate the viral
proteins.
 The scientists with the help of rDNA technology have transferred the genes
for some viral sheath proteins to vaccinia virus which was used against small
pox.

3.  Vaccines produced by gene cloning are non contaminated and safe as
they contain only coat proteins against which antibodies are produced.
 Vaccines against viral hepatitis influenza, herpes simplex virus, virus induced
foot and mouth disease in animals are being produced by gene cloning.

4. 2. Hormones
 Insulin was commercially produced in 1982 through biogenetic or rDNA
technology.
 Its medicinal use was approved by food and drug administration (FDA) of
the USA in the same year.
 The human insulin gene has been cloned in large quantities in E. coli
bacterium that can be used for synthesising insulin.
 Humilin is the commercially available genetically engineered insulin.

5. 3. Lymphokines
 They are proteins regulating the immune system in human body.
 α-interferon is an example of lymphokines that is used to fight viral diseases
(such as hepatitis, herpes and common cold) and cancer. Such drugs can
be manufactured in large quantities in bacterial cell.
 Lymphokines are also helpful in AIDS.
 Interleukin-ll is a commercially available genetically engineered substance
that stimulates the multiplication of lymphocytes.

6. 4. Somatostatin
 It is used in some of the growth related abnormalities. This drug appears to
be species and the polypeptide obtained from other mammals has no
effect on human, hence it is extracted from the hypothalamus of cadavers.
 Genetic engineering has helped in the chemical synthesis of gene which is
joined to the pBR 322 plasmid DNA and cloned into a bacterium. This
trasnformed bacterium is converted into somatostatin synthesising factory.

7. 5. Production of Blood Clotting Factors
 Blockage of coronary arteries by cholesterol or blood clots causes heart
attack. Plasminogen is a substance found in blood clots.
 Genetically engineered tissue plasminogen Activator (tPA) enzyme is used
to dissolve these clots in individuals who have suffered heart attacks.

8. 6. Cancer
 Antibodies cloned from a single source and targeted for a specific antigen
(monoclonal antibodies) have proved useful in the treatment of cancer.
 Monoclonal antibodies have been targeted with radioactive elements or
cytotoxins (eg. Ricin from castor seed) to make them more deadly.
 Such antibodies seek cancer cells and kill them with their radioactiveity or
toxins.