APPLICATIONS OF GENETIC ENGINEERING AND BIOTECHNOLOGY
Applications of Genetic Engineering and Biotechnology in medicine and agriculture
Ethical issues from the use of technology
BIOPHARMACEUTICAL PRODUCTS AND VACCINES
Genetic engineering, biotechnology and genome editing
➔ Biotechnology
o Living organisms to create products or processes to improve quality of life
o Science to ancient civilisation when microbes used to make wine, beer,
vinegar, bread and cheese products
o Modern Biotech started after recombinant DNA technology developed
(move molecules of DNA between organisms)
o Modern industry with revolutionised medicine, agriculture and industries
➔ Genetic engineering and genetic modification (GMO)
o Ability to manipulate DNA in vitro and introduce genes into living cells to
generate new varieties of plants, animal and organisms with specific traits
o Genetic engineering involves use of recombinant DNA technologies to add
gene or genes to genome and involve gene removal
o Genetically modified organisms (GMOs) form
➔ Genome editing (GEd)
o Potentially edit DNA in vivo to introduce specific mutations in precise manner
without introducing additional DNA into recipient organism
Biopharmaceutical products and vaccines
➔ GMOs used in pharmaceutical industry for production of gene products and
therapeutic proteins to treat diseases
o Gene products and proteins produced in host types to treat diseases
➔ Biopharming: valuable proteins in genetically modified (GM) animals and plants
o Antibodies and vaccines
Recombinant protein production in bacteria
➔ Human insulin (Human®) first commercial biotech product manufactured by
recombinant DNA technology for therapeutic use
o Insulin was chemically extracted from pancreas of cows and pigs at abattoirs
➔ Human growth hormone gene was cloned and turned into commercial product to
treat children suffering from form of dwarfism
➔ Therapeutic proteins produced by expressing human genes in bacteria
➔ Human gene cloned into plasmid and recombinant vector introduced into bacteria
host which is grown in large industrial fermenters and recombinant human proteins
recovered and purified from bacterial cultures
,Active insulin contain an A and B subunit joined by disulfide bounds
Transforming E.coli:
1. Gene A subunit and Gene B subunit separates each into a different plasmid vector
with promoter, lacZ gene and antibiotic resistance gene
2. β-gal or insulin A fusion protein accumulates in cell from its vector and β-gal or
insulin B fusion protein accumulates in cell from its vector
3. Extracted and purified β-gal or insulin fusion proteins from each cell
4. Treated with cyanogen bromide to release A and B chains
5. Purified and mixed A and B chains forms functional insulin where A and B subunits
are joined the a disulfide bond to form active insulin
Biopharmaceutical production in transgenic animal hosts
➔ Bacterial expression systems fail to properly process post-translational modifications
(glycosylation or phosphorylation) due to being prokaryotic required for eukaryotic
proteins to be fully functional
➔ Eukaryotic proteins produced in bacterial cells not fold into proper three-dimensional
conformation required for functionality
o Prokaryote bacteria no ability to fold properly as protein product needs post-
translational modification and does not occur in prokaryotic cells
➔ Transgenic animals systems as yeast cells, insect cell lines or transgenic animals
therefore act as bioreactors or biofactories
o Chickens easier to rear and more efficient as biofactors as they are efficient in glycosylating
recombinant proteins
o Antithrombin (anti-clotting protein in blood) 1st drug produced in milk of farm animals and then human
antithrombin gene expressed in mammary glands of goats
o Single goat produces equivalent amount of antithrombin that requires human blood collections
o Kauma made from eggs of GM chickens expressing recombinant form of enzyme lysosomal acid lipase
or sebelipase alfa used as medication for treatment of lysosomal acid lipase deficiency
,Recombinant vaccine production
Vaccines
➔ Inactivated vaccines: prepared from killed versions of infectious virus or bacteria i.e.
Rabies and influenza
o Bacteria killed by heat (denatured) and dead pathogen injected in organism
Kill bacteria you want antibodies against
o Antibodies form in organism that heat-killed pathogen is inserted into
o Virulent bacterium or virus enters and does not cause disease
➔ Attenuated vaccines: live viruses or bacteria that no longer reproduces but causes a
mild form of diseases i.e. Tuberculosis, cholera and chickenpox
➔ Subunit vaccines: one or more antigenic surface proteins from virus or bacterium not
the entire virus or bacterium through genetic engineering
o Johnson & Johnson SARS-Cox-2 vaccine
Gardasil® subunit vaccine targets four strains of human papillomavirus (HPV) that causes
cervical cancer. National Department of Heath introduced HPV vaccination as strategy for
cervical cancer prevention in SA (cervical cancer 2nd common cancer in women)
Vaccine production in plants
Advantages for expressing recombinant proteins
➔ Transgenic plant easily grown and vegetatively propagated in greenhouse or field
providing constant source of recombinant protein
➔ Cost of expressing recombinant protein in transgenic plant lower than same protein
created in bacteria, yeast or mammalian cells
➔ Antibodies against Ebolavirus expressed in tobacco leaves: Ebola monoclonal
antibody genes from transgenic mice introduced into tobacco plants which expressed
high quantities of antibody proteins which is isolated and purified for use in humans
Disadvantages: temperature sensitivity, sterile conditions for administering, time and money
Edible vaccines expressing a vaccine in fruit or vegetable
Cholera in potatoes and hepatitis B in bananas
1. Gene from human pathogen inserted in vector and vector introduced into plant cell
2. Leaf segments sprout into whole plants carrying the gene from the human pathogen
3. Eating plant based food triggers immune response developing antibodies to
pathogen therefore when pathogen affects no disease or is mild and can recover
, DNA-based vaccines
➔ Inserted recombinant DNA expresses pathogen-specific proteins tiggering an
immune response with developed antibodies
➔ DNA encoding proteins from particular pathogen inserted into plasmid vectors and
injected directly into individual or delivered via viral vector similar to way certain
viruses are used for gene therapy
➔ mRNA vaccines, an mRNA stabilised and injected, translated into antigenic protein
that stimulates immune system to produce antibodies and recover from disease
o Pfizer SARS-Cov-2 vaccine
Trials with DNA expressing pre-membrane and envelope proteins of Zika virus (ZIKV causes
microcephaly) created high levels of antibodies in mice and Rhesus monkeys capable of neutralising
ZIKV and protecting against ZIKV infection involved in human clinical trials
mRNA vaccines: 2023 Nobel Prize of medicine
➔ Katalin Kariko and Drew Weissman: discoveries concerning nucleoside base
modifications enabled development of effective mRNA vaccines against COVID-19
o Chemicals modifications of nucleotides synthesising mRNA
➔ Pfizer or BioNTech (ComirnatyTM) and Modern (SpikeVaxTM)
➔ mRNA stabilised in lipid nanoparticles and injected is translated into an antigenic
protein that stimulates the immune system to produce antibodies
o mRNA translated into Spike protein that triggers immune response
developing antibodies against viral Spike protein
➔ Efficient
mRNA encodes Spike protein carrying the genetic code
Lipids emulsify and coat mRNA and protect against RNAses
Salts stabilised the pH
Sucrose stabilised the mRNA
Water to dilute mRNA
GENETICALLY MODIFIED PLANTS AND ANIMALS: GM FOODS
Selective breeding vs agriculture biotechnology
Genetic engineering revolutionised agriculture
Traditional breeding: cross with traditional donor containing a resistant gene forming the
new variety. Disadvantage -> traits from commercial variety that are unwanted i.e. alkaloid
production are contained in new variety. Remove -> back-crossing traditional donors to
retain only the viral resistant from traditional donor not the original genes in new variety
Mutation breeding: no control to where radiation affects genome and no control over the
amount of genomes modified therefore screen for desired trait or gene
Genetic modification (GM): isolate viral resistant gene from traditional donor gene and
insert it into a plasmid where it is inserted in an organism. Disadvantage -> no control of
insertion position and number of copies inserted new gene
Applications of Genetic Engineering and Biotechnology in medicine and agriculture
Ethical issues from the use of technology
BIOPHARMACEUTICAL PRODUCTS AND VACCINES
Genetic engineering, biotechnology and genome editing
➔ Biotechnology
o Living organisms to create products or processes to improve quality of life
o Science to ancient civilisation when microbes used to make wine, beer,
vinegar, bread and cheese products
o Modern Biotech started after recombinant DNA technology developed
(move molecules of DNA between organisms)
o Modern industry with revolutionised medicine, agriculture and industries
➔ Genetic engineering and genetic modification (GMO)
o Ability to manipulate DNA in vitro and introduce genes into living cells to
generate new varieties of plants, animal and organisms with specific traits
o Genetic engineering involves use of recombinant DNA technologies to add
gene or genes to genome and involve gene removal
o Genetically modified organisms (GMOs) form
➔ Genome editing (GEd)
o Potentially edit DNA in vivo to introduce specific mutations in precise manner
without introducing additional DNA into recipient organism
Biopharmaceutical products and vaccines
➔ GMOs used in pharmaceutical industry for production of gene products and
therapeutic proteins to treat diseases
o Gene products and proteins produced in host types to treat diseases
➔ Biopharming: valuable proteins in genetically modified (GM) animals and plants
o Antibodies and vaccines
Recombinant protein production in bacteria
➔ Human insulin (Human®) first commercial biotech product manufactured by
recombinant DNA technology for therapeutic use
o Insulin was chemically extracted from pancreas of cows and pigs at abattoirs
➔ Human growth hormone gene was cloned and turned into commercial product to
treat children suffering from form of dwarfism
➔ Therapeutic proteins produced by expressing human genes in bacteria
➔ Human gene cloned into plasmid and recombinant vector introduced into bacteria
host which is grown in large industrial fermenters and recombinant human proteins
recovered and purified from bacterial cultures
,Active insulin contain an A and B subunit joined by disulfide bounds
Transforming E.coli:
1. Gene A subunit and Gene B subunit separates each into a different plasmid vector
with promoter, lacZ gene and antibiotic resistance gene
2. β-gal or insulin A fusion protein accumulates in cell from its vector and β-gal or
insulin B fusion protein accumulates in cell from its vector
3. Extracted and purified β-gal or insulin fusion proteins from each cell
4. Treated with cyanogen bromide to release A and B chains
5. Purified and mixed A and B chains forms functional insulin where A and B subunits
are joined the a disulfide bond to form active insulin
Biopharmaceutical production in transgenic animal hosts
➔ Bacterial expression systems fail to properly process post-translational modifications
(glycosylation or phosphorylation) due to being prokaryotic required for eukaryotic
proteins to be fully functional
➔ Eukaryotic proteins produced in bacterial cells not fold into proper three-dimensional
conformation required for functionality
o Prokaryote bacteria no ability to fold properly as protein product needs post-
translational modification and does not occur in prokaryotic cells
➔ Transgenic animals systems as yeast cells, insect cell lines or transgenic animals
therefore act as bioreactors or biofactories
o Chickens easier to rear and more efficient as biofactors as they are efficient in glycosylating
recombinant proteins
o Antithrombin (anti-clotting protein in blood) 1st drug produced in milk of farm animals and then human
antithrombin gene expressed in mammary glands of goats
o Single goat produces equivalent amount of antithrombin that requires human blood collections
o Kauma made from eggs of GM chickens expressing recombinant form of enzyme lysosomal acid lipase
or sebelipase alfa used as medication for treatment of lysosomal acid lipase deficiency
,Recombinant vaccine production
Vaccines
➔ Inactivated vaccines: prepared from killed versions of infectious virus or bacteria i.e.
Rabies and influenza
o Bacteria killed by heat (denatured) and dead pathogen injected in organism
Kill bacteria you want antibodies against
o Antibodies form in organism that heat-killed pathogen is inserted into
o Virulent bacterium or virus enters and does not cause disease
➔ Attenuated vaccines: live viruses or bacteria that no longer reproduces but causes a
mild form of diseases i.e. Tuberculosis, cholera and chickenpox
➔ Subunit vaccines: one or more antigenic surface proteins from virus or bacterium not
the entire virus or bacterium through genetic engineering
o Johnson & Johnson SARS-Cox-2 vaccine
Gardasil® subunit vaccine targets four strains of human papillomavirus (HPV) that causes
cervical cancer. National Department of Heath introduced HPV vaccination as strategy for
cervical cancer prevention in SA (cervical cancer 2nd common cancer in women)
Vaccine production in plants
Advantages for expressing recombinant proteins
➔ Transgenic plant easily grown and vegetatively propagated in greenhouse or field
providing constant source of recombinant protein
➔ Cost of expressing recombinant protein in transgenic plant lower than same protein
created in bacteria, yeast or mammalian cells
➔ Antibodies against Ebolavirus expressed in tobacco leaves: Ebola monoclonal
antibody genes from transgenic mice introduced into tobacco plants which expressed
high quantities of antibody proteins which is isolated and purified for use in humans
Disadvantages: temperature sensitivity, sterile conditions for administering, time and money
Edible vaccines expressing a vaccine in fruit or vegetable
Cholera in potatoes and hepatitis B in bananas
1. Gene from human pathogen inserted in vector and vector introduced into plant cell
2. Leaf segments sprout into whole plants carrying the gene from the human pathogen
3. Eating plant based food triggers immune response developing antibodies to
pathogen therefore when pathogen affects no disease or is mild and can recover
, DNA-based vaccines
➔ Inserted recombinant DNA expresses pathogen-specific proteins tiggering an
immune response with developed antibodies
➔ DNA encoding proteins from particular pathogen inserted into plasmid vectors and
injected directly into individual or delivered via viral vector similar to way certain
viruses are used for gene therapy
➔ mRNA vaccines, an mRNA stabilised and injected, translated into antigenic protein
that stimulates immune system to produce antibodies and recover from disease
o Pfizer SARS-Cov-2 vaccine
Trials with DNA expressing pre-membrane and envelope proteins of Zika virus (ZIKV causes
microcephaly) created high levels of antibodies in mice and Rhesus monkeys capable of neutralising
ZIKV and protecting against ZIKV infection involved in human clinical trials
mRNA vaccines: 2023 Nobel Prize of medicine
➔ Katalin Kariko and Drew Weissman: discoveries concerning nucleoside base
modifications enabled development of effective mRNA vaccines against COVID-19
o Chemicals modifications of nucleotides synthesising mRNA
➔ Pfizer or BioNTech (ComirnatyTM) and Modern (SpikeVaxTM)
➔ mRNA stabilised in lipid nanoparticles and injected is translated into an antigenic
protein that stimulates the immune system to produce antibodies
o mRNA translated into Spike protein that triggers immune response
developing antibodies against viral Spike protein
➔ Efficient
mRNA encodes Spike protein carrying the genetic code
Lipids emulsify and coat mRNA and protect against RNAses
Salts stabilised the pH
Sucrose stabilised the mRNA
Water to dilute mRNA
GENETICALLY MODIFIED PLANTS AND ANIMALS: GM FOODS
Selective breeding vs agriculture biotechnology
Genetic engineering revolutionised agriculture
Traditional breeding: cross with traditional donor containing a resistant gene forming the
new variety. Disadvantage -> traits from commercial variety that are unwanted i.e. alkaloid
production are contained in new variety. Remove -> back-crossing traditional donors to
retain only the viral resistant from traditional donor not the original genes in new variety
Mutation breeding: no control to where radiation affects genome and no control over the
amount of genomes modified therefore screen for desired trait or gene
Genetic modification (GM): isolate viral resistant gene from traditional donor gene and
insert it into a plasmid where it is inserted in an organism. Disadvantage -> no control of
insertion position and number of copies inserted new gene
