Genetic Engineering Products
Overview of Biotechnology
Biotechnology is the use of biological techniques and engineered organisms to make products or plants and animals that have desired traits.Learning Objectives
Describe the historical development of biotechnologyKey Takeaways
Key Points
- For thousands of years, humankind has used biotechnology in agriculture, food production, and medicine.
- In the late 20th and early 21st century, biotechnology has expanded to include new and diverse sciences such as genomics, recombinant gene technologies, applied immunology, and development of pharmaceutical therapies and diganostic tests.
- Biotechnology has applications in four major industrial areas, including health care (medical), crop production and agriculture, non food (industrial) uses of crops and other products (e.g. biodegradable plastics, vegetable oil, biofuels), and environmental uses.
Key Terms
- nanotechnology: the science and technology of creating nanoparticles and of manufacturing machines which have sizes within the range of nanometres

Biotechnology: Brewing (fermentation of beer) was an early application of biotechnology.
In its broadest definition, biotechnology is the application of biological techniques and engineered organisms to make products or modify plants and animals to carry desired traits. This definition also extends to the use of various human cells and other body parts to produce desirable products. Bioindustry refers to the cluster of companies that produce engineered biological products and their supporting businesses. Biotechnology refers to the use of the biological sciences (such as gene manipulation), often in combination with other sciences (such as materials sciences, nanotechnology, and computer software), to discover, evaluate and develop products for bioindustry. Biotechnology products have made it easier to detect and diagnose illnesses. Many of these new techniques are easier to use and some, such as pregnancy testing, can even be used at home. More than 400 clinical diagnostic devices using biotechnology products are in use today. The most important are screening techniques to protect the blood supply against contamination by AIDS and the hepatitis B and C viruses.
Applications of Genetic Engineering
Genetic engineering means the manipulation of organisms to make useful products and it has broad applications.Learning Objectives
Describe the major applications of genetic engineeringKey Takeaways
Key Points
- Genetic engineering has applications in medicine, research, industry and agriculture and can be used on a wide range of plants, animals and microorganisms.
- In medicine, genetic engineering has been used to mass-produce insulin, human growth hormones, follistim (for treating infertility), human albumin, monoclonal antibodies, antihemophilic factors, vaccines, and many other drugs.
- In research, organisms are genetically engineered to discover the functions of certain genes.
- Industrial applications include transforming microorganisms such as bacteria or yeast, or insect mammalian cells with a gene coding for a useful protein. Mass quantities of the protein can be produced by growing the transformed organism in bioreactors using fermentation, then purifying the protein.
- Genetic engineering is also used in agriculture to create genetically-modified crops or genetically-modified organisms.
Key Terms
- biotechnology: The use of living organisms (especially microorganisms) in industrial, agricultural, medical, and other technological applications.
- cloning: The production of a cloned embryo by transplanting the nucleus of a somatic cell into an ovum.
New DNA may be inserted in the host genome by first isolating and copying the genetic material of interest, using molecular-cloning methods to generate a DNA sequence; or by synthesizing the DNA, and then inserting this construct into the host organism. Genes may be removed, or "knocked out", using a nuclease.

Genetically manipulated mice: Laboratory mice are genetically manipulated by deleting a gene for use in biomedical research.
Genetic engineering has produced a variety of drugs and hormones for medical use. For example, one of its earliest uses in pharmaceuticals was gene splicing to manufacture large amounts of insulin, made using cells of E. coli bacteria. Interferon, which is used to eliminate certain viruses and kill cancer cells, also is a product of genetic engineering, as are tissue plasminogen activator and urokinase, which are used to dissolve blood clots.
Another byproduct is a type of human growth hormone; it's used to treat dwarfism and is produced through genetically-engineered bacteria and yeasts. The evolving field of gene therapy involves manipulating human genes to treat or cure genetic diseases and disorders. Modified plasmids or viruses often are the messengers to deliver genetic material to the body's cells, resulting in the production of substances that should correct the illness. Sometimes cells are genetically altered inside the body; other times scientists modify them in the laboratory and return them to the patient's body.
Since the 1990s, gene therapy has been used in clinical trials to treat diseases and conditions such as AIDS, cystic fibrosis, cancer, and high cholesterol. Drawbacks of gene therapy are that sometimes the person's immune system destroys the cells that have been genetically altered, and also that it is hard to get the genetic material into enough cells to have the desired effect.
Biochemical Products of Recombinant DNA Technology
Many practical applications of recombinant DNA are found in human and veterinary medicine, in agriculture, and in bioengineering.Learning Objectives
Describe the advances made possible by recombinant DNA technologyKey Takeaways
Key Points
- Recombinant DNA (rDNA) is widely used in biotechnology, medicine and research. Proteins and other products that result from the use of rDNA technology are found in essentially every western pharmacy, doctor's or veterinarian's office, medical testing laboratory, and biological research laboratory.
- Organisms that have been manipulated using recombinant DNA technology, and products derived from those organisms have found their way into many farms, supermarkets, home medicine cabinets, and even pet shops.
- Biochemical products of recombinant DNA technology in medicine and research include: human recombinant insulin, growth hormone, blood clotting factors, hepatitis B vaccine, and diagnosis of HIV infection.
- Biochemical products of recombinant DNA technology in agriculture include: golden rice, herbicide-resistant crops, and insect-resistant crops.
Key Terms
- retinoblastoma: A malignant tumour of the retina; a hereditary condition found mostly in children.
- neurofibromatosis: A genetic disorder characterized by the presence of multiple neurofibromas under the skin
- cystic fibrosis: An inherited condition in which the exocrine glands produce abnormally viscous mucus, causing chronic respiratory and digestive problems.
- recombinant DNA technology: the process of taking a gene from one organism and inserting it into the DNA of another
Construction of recombinant DNA: A foreign DNA fragment is inserted into a plasmid vector. In this example, the gene indicated by the white color is inactivated upon insertion of the foreign DNA fragment.
Recombinant DNA technology, apart from being an important tool of scientific research, has also played a vital role in the diagnosis and treatment of various diseases, especially those belonging to genetic disorders.
Some of the recent advances made possible by recombinant DNA technology are:
1. Isolating proteins in large quantities: many recombinant products are now available, including follicle stimulating hormone (FSH), Follistim AQ vial, growth hormone, insulin and some other proteins.
2. Making possible mutation identification: due to this technology, people can be easily tested for mutated protein presence that can lead to breast cancer, neurofibromatosis, and retinoblastoma.
3. Hereditary diseases carrier diagnosis: tests now available to determine if a person is carrying the gene for cystic fibrosis, the Tay-Sachs diseases, Huntington's disease or Duchenne muscular dystrophy.
4. Gene transfer from one organism to other: the advanced gene therapy can benefit people with cystic fibrosis, vascular disease, rheumatoid arthritis and specific types of cancers.
Mammalian Gene Expression in Bacteria
Bacterial genetics can be manipulated to allow for mammalian gene expression systems established in bacteria.Learning Objectives
Describe the sequence of events in a genetically engineered expression systemKey Takeaways
Key Points
- Recently improved methods of DNA chemical synthesis, combined with recombinant DNA technology, permit the design and relatively rapid synthesis of modest-sized genes that can be incorporated into prokaryotic cells for gene expression using genetic engineering.
- The feasibility of this general approach was first demonstrated by the synthesis and expression of the mammalian peptide somatostatin in Escherichia coli.
- Mammalian gene expression can be achieved in many expression hosts by utilizing the host's naturally occurring machinery.
Key Terms
- ribozyme: A fragment of RNA that can act as an enzyme.
- plasmid: A circle of double-stranded DNA that is separate from the chromosomes, which is found in bacteria and protozoa.
The genetically engineered expression system contains the appropriate DNA sequence for the gene of choice which is engineered into a plasmid that is introduced into a bacteria host. The molecular machinery that is required to transcribe the DNA is derived from the innate and naturally occurring machinery in the host. The DNA is then transcribed into mRNA and then translated into protein products.
In a genetically engineered system, this entire process of gene expression may be induced depending on the plasmid used. In the broadest sense, mammalian gene expression includes every living cell but the term is more normally used to refer to expression as a laboratory tool. An expression system is therefore often artificial in some manner. Viruses and bacteria are an excellent example of expression systems.
The oldest and most widely used expression systems are cell-based. Expression is often done to a very high level and therefore referred to as overexpression. There are many ways to introduce foreign DNA to a cell for expression, and there are many different host cells which may be used for expression. Each expression system also has distinct advantages and liabilities.
Expression systems are normally referred to by the host and the DNA source or the delivery mechanism for the genetic material. For example, common bacterial hosts are E.coli and B. subtilis. With E. coli, DNA is normally introduced in a plasmid expression vector. The techniques for overexpression in E. coli work by increasing the number of copies of the gene or increasing the binding strength of the promoter region so as to assist transcription.
Bacterial Flora: E. coli is one of the most popular hosts for artificial gene expression.
Mammalian Proteins and Products
Genetic engineering enables scientists to create plants, animals, and microorganisms by manipulating genes.Learning Objectives
Explain the advantages and disadvantages of producing genetically engineered proteins in bacteriaKey Takeaways
Key Points
- Systems used for mass production of recombinant human proteins include bacteria, viruses, mammalian cells, animals, and plants.
- Most processes come with advantages and disadvantages, mostly low cost. However, mammalian proteins and products produced in animals bare ethical issues.
- A large number of mammalian proteins are being manufactured by pharmaceutical companies for use in the treatment of human diseases.
Key Terms
- bioreactors: A device that supports a biologically active environment.

Synthetic Insulin: human insulin produced by recombinant DNA technology.
Many mammalian proteins are produced by genetic engineering. These include, in particular, an assortment of hormones and proteins for blood clotting and other blood processes. For example, tissue plasminogen activator (TPA) is a blood protein that scavenges and dissolves blood clots that may form in the final stages of the healing process. TPA is primarily used in heart patients or others suffering from poor circulation to prevent the development of clots that can be life-threatening. Heart disease is a leading cause of death in many developed countries, especially in the United States, so microbially produced TPA is in high demand. In contrast to TPA, the blood clotting factors VII, VIII, and IX are critically important for the formation of blood clots. Hemophiliacs suffer from a deficiency of one or more clotting factors and can therefore be treated with microbially produced clotting factors. In the past hemophiliacs have been treated with clotting factor extracts from pooled human blood, some of which was contaminated with viruses such as HIV and hepatitis C, putting hemophiliacs at high risk for contracting these diseases. Recombinant clotting factors have eliminated this problem.