INTRODUCTION TO BIOTECHNOLOGY: A TEACHER’S COMPREHENSIVE GUIDE
Welcome, future pharmacists and healthcare professionals!
Biotechnology is a branch of biology involving the use of living organisms and bioprocesses in engineering, technology, medicine, and other fields using bioproducts. The term biotechnology indicates the use of living organisms or their products for modifying the human health and environment.
Transgenic plants and animals are widely used in agricultural field; in humans, devastating diseases are being treated by gene therapy; and in the environment, biotechnology is used in water and land management and also in the management of pollution resulting from over-industrialisation. Therefore, biotechnology is a collection of biological, chemical, and engineering disciplines with various uses in agricultural, medical, industrial and environmental situations.
Dpharmguru’s exam insights:
In my years of teaching biotechnology, I have observed that students often get overwhelmed by the timeline of discoveries. Remember: The key milestones are the discovery of DNA structure (Watson & Crick, 1953), the first genetic engineering experiment (Boyer & Cohen, 1973), and the sequencing of the human genome (2003). These are frequently tested in exams!
HISTORICAL BACKGROUND OF BIOTECHNOLOGY
The earlier formative works which made significant contributions in the growth of biotechnology are listed below:
| Year | Summary of the Discoveries |
|---|---|
| 1665 | Robert Hooke observed tiny microscopic structures under the first microscope and coined the word cell. |
| 1830 | Robert Brown identified an opaque area in plant cells and called it nucleus. |
| 1857 | Biologists observed small rod-like bodies in dividing cells, and called them chromosomes. |
| 1869 | Johann Friedrich Miescher isolated nuclein, which at present is called DNA. |
| 1879 | Albrecht Kossel discovered the nucleic acid composition, i.e., adenine, thymine, cytosine, guanine, and uracil. |
| 1882 | Edouard van Beneden found out that every species characteristically possesses a specific number of chromosomes. |
| 1902 | Walter S. Sutton reported that each chromosome paired with another physically similar pair and then got separated during meiosis. |
| 1907 | Tissue culture techniques were developed. |
| 1909 | Wilhelm Ludvig Johannsen coined the term genes. |
| 1919 | Thomas Hunt Morgan identified XY male and XX female chromosomes and suggested that some traits are sex-linked. |
| 1930 | Electron microscope was invented with the help of which the researchers viewed viruses. |
| 1944 | Oswald T. Avery along with his colleagues demonstrated that DNA is the carrier of genetic information. |
| 1953 | James Watson and Francis Crick proposed a double helix molecular structure of DNA based on Rosalind Franklin’s model. |
| 1961 | Francois Jacob and Jacques Monod suggested that differential gene expression causes differences in the structure and function of cells. |
| 1964 | Marshall Nirenberg cracked genetic code. |
| 1970 | First restriction enzyme was isolated. |
| 1973 | Herbert W. Boyer and Stanley N. Cohen performed the first genetic engineering experiment by linking toad genes with E. coli bacteria. |
| 1976 | J. Michael Bishop and Harold E. Varmus discovered oncogenes. |
| 1978 | Yuet Wai Kan established molecular techniques to allow the first foetal test for identifying sickle cell anaemia. |
| 1979 | Genentech Inc. developed synthetic human growth hormone. |
| 1980 | Virus-fighting interferon was cloned. |
| 1981 | Transgenic mice and transgenic fruit flies were produced. |
| 1987 | William J. Rutter produced the first commercial genetically engineered vaccine against hepatitis B. |
| 1990 | Chymosin became the first product of genetic engineering to be introduced into the food supply. |
| 1991 | The gene implicated in the inherited form of breast cancer was discovered. |
| 1992 | Techniques for testing embryos for inherited diseases were developed. |
| 1996 | Dolly, the sheep was cloned from a cell from an adult sheep making it the first cloned organism. |
| 1999 | New Zealand researchers developed a new vaccine for bovine and human tuberculosis. |
| 2003 | The human genome was sequenced. |
| 2004 | UN Food and Agriculture Organisation endorsed biotech crops. |
| 2005 | FDA approved Avastin (the first anti-angiogenic drug for cancer). |
| 2006 | FDA approved Gardasil recombinant vaccine against HPV. |
| 2007 | USDA granted Dow AgroSciences the first regulatory approval for a plant-made vaccine. |
| 2008 | FDA approved the H5N1 vaccine (the first vaccine approved for avian flu). |
| 2009 | FDA approved the first genetically engineered animal for production of a recombinant form of human anti-thrombin. |
Dpharmguru’s exam insights:
A common exam question is: “Who discovered the structure of DNA?” The answer is Watson and Crick in 1953, based on Rosalind Franklin’s X-ray diffraction data. Also, remember that the first genetic engineering experiment was performed by Boyer and Cohen in 1973. These are landmark events in biotechnology history!
APPLICATIONS OF BIOTECHNOLOGY IN PHARMACEUTICAL SCIENCES
1. Medicine
a) Drug Production
Most of the traditional pharmaceutical drugs used for treating the symptoms of a disease are simpler molecules found through trials and errors. Small molecules are manufactured chemically, but the larger ones are created by human cells, bacterial cells, yeast cells, and animal or plant cells. Modern biotechnology involves the use of genetically altered microorganisms (e.g., E. coli or yeast) for producing insulin or antibiotics via synthetic means.
Modern biotechnology can also be used for producing plant-made pharmaceuticals. Biotechnology is also used in the development of molecular diagnostic devices used to define the target patient population for a given biopharmaceutical. For example, herceptin was the first drug to be used with a matching diagnostic test for treating breast cancer in women whose cancer cells expressed HER2 protein.
b) Pharmacogenomics
Pharmacogenomics is the study of how the genetic inheritance of an individual affects his/her body’s response to drugs. The term pharmacogenomics was derived from the words pharmacology and genomics, thus it involves studying the relationship between pharmaceuticals and genetics. Pharmacogenomics aims to design and produce drugs adapted to each individual’s genetic makeup.
Dpharmguru’s exam insights:
Pharmacogenomics is the study of how genes affect drug response. Remember: “Pharmacogenomics = Personalized Medicine.” This is a growing field and is frequently tested in exams. Herceptin is a classic example of a targeted therapy based on genetic testing (HER2 positive breast cancer).
c) Gene Therapy
Gene therapy is used for the treatment of genetic and acquired diseases like cancer and AIDS. Gene therapy utilises normal genes for supplementing or replacing the defective genes or for strengthening immunity. This therapy targets either the somatic cells (i.e., body) or the gametes (i.e., egg and sperm).
In somatic gene therapy, the recipient’s genome is altered; however, this alteration is not passed on to the next generation. On the other hand, in germline gene therapy, the egg and sperm cells of the parents are altered to be passed on to their offspring.
d) Genetic Testing
Genetic testing involves direct examination of the DNA, and is used for:
- Carrier screening, or identifying unaffected individuals who carry one copy of a gene for a disease that requires two copies for the disease to manifest.
- Confirming the diagnosis of symptomatic individuals.
- Determining sex.
- Forensic/identity testing.
- New-born screening.
- Prenatal diagnostic screening.
- Pre-symptomatic testing for determining the risk of developing adult-onset cancers.
- Pre-symptomatic testing for predicting adult-onset disorders.
2. Cloning
In this method, nucleus from one cell is removed and is transferred to an unfertilised egg cell whose nucleus has either been deactivated or removed. Cloning can be done in the following two ways:
- Reproductive Cloning: In this method, the egg cell after a few divisions is transferred to a uterus for its development into a foetus that is genetically identical to the donor of the original nucleus.
- Therapeutic Cloning: In this method, the egg is placed in a petri dish for its development into embryonic stem cells that are potential for treating several ailments.
Dpharmguru’s exam insights:
The difference between reproductive and therapeutic cloning is frequently tested. Reproductive cloning creates a whole organism (e.g., Dolly the sheep), while therapeutic cloning creates stem cells for treatment. Remember: “Reproductive = Whole organism, Therapeutic = Stem cells.”
3. Agriculture
Biotechnology in agricultural field is used for the following purposes:
a) Crop Yield
For increasing the crop yield, one or two genes are transferred to a highly developed crop variety for imparting new character. Some genetic characteristics related to yield (e.g., enhanced growth) can be controlled by various genes, each posing a nominal effect on the yield.
b) Reduced Vulnerability of Crops to Environmental Stresses
Such crops which can be made resistant to biotic and abiotic stresses can be developed with the help of genes; for example, drought and salty soil are the two limiting factors in crop productivity.
c) Increased Nutritional Qualities
The nutritional value of proteins contained in foods can be enhanced; for example, proteins in legumes and cereals can be transformed such that they also provide amino acids required in the balanced diet of humans.
d) Reduced Dependence on Fertilisers
Modern biotechnology can also be used to reduce the dependence of farmers on agrochemicals; for example, Bacillus thuringiensis (Bt) is a soil bacterium that produces a protein having insecticidal properties. Conventionally, these bacteria were used to produce an insecticidal spray by a fermentation process. In this form, the Bt toxin occurs as an inactive protoxin, which becomes effective when digested by an insect. There are several Bt toxins and each has specificity for some target insects.
e) Production of Novel Substances in Crop Plants
Biotechnology is also applied for novel uses apart from food; for example, oilseed is genetically modified to produce fatty acids for detergents, substitute fuels, and petrochemicals. Potatoes, tomatoes, rice, tobacco, lettuce, safflowers, and other plants are genetically engineered to produce insulin and certain vaccines.
4. Biological Engineering
It is a branch of engineering that involves biotechnologies and biological science. It includes different disciplines such as biochemical engineering, biomedical engineering, bio-process engineering, biosystem engineering, etc.
SUMMARY
Biotechnology is a rapidly growing field that uses living organisms and biological processes to develop products and technologies that improve human health, agriculture, and the environment. Key applications include drug production, pharmacogenomics, gene therapy, genetic testing, cloning, agricultural biotechnology, and biological engineering. Understanding the history and applications of biotechnology is essential for pharmacy students and healthcare professionals.
Dpharmguru’s exam insights:
Biotechnology is transforming medicine and pharmacy. In exams, pay special attention to: (1) The key milestones in biotechnology history, (2) The difference between somatic and germline gene therapy, (3) The difference between reproductive and therapeutic cloning, and (4) The applications of pharmacogenomics. Remember: “Biotechnology is the future of medicine—know it well!”
REFERENCES AND FURTHER READING
- Kumar, A. (2022). Biotechnology: Principles and Applications. PharmaMed Press.
- Ratledge, C., & Kristiansen, B. (2020). Basic Biotechnology (4th ed.). Cambridge University Press.
- Glick, B. R., & Patten, C. L. (2022). Molecular Biotechnology: Principles and Applications of Recombinant DNA (6th ed.). ASM Press.
- World Health Organization (WHO). (2022). Biotechnology and Health Resources. Retrieved from https://www.who.int.
- National Institutes of Health (NIH). (2022). Biotechnology and Genomics Resources. Retrieved from https://www.nih.gov.
Disclaimer: This article is for educational purposes only and does not constitute medical advice. Always consult qualified healthcare professionals for medical concerns.
written by:
Dr. N. Sujith Kumar
