animal biotech Flashcards
A broad range of technologies using scientific and
engineering principles applied to animals used for food,
medicine, diagnostic, health, and other biological applications
animal biotech
Combining animals and biotechnology results in
advances in four primary areas:
- advacement in human health
- improvemed animal health and welfare
- enhanced animal products
- environemental & conservation benefits
uses of GMO (3)
develop new medical treatments
imrpoved food supply
enhanced understanding of animals and humans
model animals (6)
- zebrafish (brachydanio rerio)
- dogs (canis lupus familiaris)
- monkey & chimpanzee (cercopithecidae)
- mice
- drosophila
- rabit (oryctolagus cuniculus)
other model organisms
- frog- american clawed frog(xenopus laevis)
- worms (caenorhabditis elegans)
- arabidopsis thaliana
origin of zebrafish
south asia
zebrafish percentage of genes similar to human body
70 percent
zebrafish
weekly progeny:
complete embryogenesis:
development of internal organs:
weekly progeny: 200 eggs
complete embryogenesis: 120 hrs
development of internal organs: 48-72 hrs after fertilization
percetage of genetic similarity between dogs and humans
95 percent
-used to study all kinds of disease
-easily accessible
-very similarto humans
-genetically modified
mice
-low cost
-rapid generation
-small genome
- used to study of genes and genetic mutations
drosophila
-Short lifecycle
-Very docile, easy to handle
-Phylogenetically close to humans
-Used to study all kinds of
diseases
rabbit
disadvantages of using animals in testing
- costly and time-consuming
- does not completely mimic human response to various testing
- questionable ethically
involves the use of animals for pre-clinical testing before allowed in humans.
FDA Phase testing
If the new drug candidate has proven to be non-toxic and has benefit, then it can be awarded an ____________ (IND)
status.
Investigational New Drug
years, tested on, purpose of preclinical tesing for drug approval
years: 3.5
tested on: animals in the lab
purpose: assess safety and biological activity & file IND at FDA
years, tested on, purpose of phase I for drug approval
years: 1
tested on: 20-80 healthy volunteers
purpose: determine safety and dosage
years, tested on, purpose of phase II for drug approval
years: 2
tested on: 100-300 patient volunteers
purpose: evaluate effectiveness & side-effects
years, tested on, purpose of phase III for drug approval
years: 3
tested on: 1000-3000
purpose: verify effectiveness and monitor adverse reactions from long-term use & file IND at FDA
years, tested on, purpose of FDA for drug approval
years: 2.5
tested on: N/A
purpose: review process/approval
purpose of phase IV for drug approval
purpose: additional testing after approval required by FDA
three R’s in animal testing
- reduce number of higher species for testing
- replace animals with alternative models if possible
- refine tests and experiments to ensure most humane conditions possible
alternatives to the use of animals (2)
human cell cultures
computed-generated models
year-use of insulin as a treatment against diabetes in dogs.
1920
year - discovery of the effects of anesthesia in laboratory rats
1930
year - the effectiveness of penicillin as an antibiotic was proven in mice
1940
year- development of hip prostheses following studies in sheep
1950
year - the antidepressant effect of some molecules that act on the brain was demonstrated
1960
year - manufacture of the asthma inhaler after tests on guinea pigs
1970
year - implementation of magnetic resonance imaging (MRI) as a diagnostic tool in pigs
1980
year - discovery of antiretroviral drugs against HIV in monkeys
1990
year - development of a vaccine against cervical cancer in rabbits
2000
year - use of stem cells to repair heart tissue in zebrafish
2010
animals that stably incorporated engineered DNA into its
germ-line; such organism is able to pass the transgene onto all the offspring;
transgenic animals
true or false: all cells of a transgenic organism contain the transgene
true
w
Some techniques that can used to introduce new genetic
material into animals (7)
- retrovirus-mediated transgenics
- pronuclear microinjection
- ESCs method
- sperm-mediated transfer
- gene guns
- knockouts
- knock-in or gene knock-in
– accomplished by infecting mouse embryos with retroviruses before the embryos are implanted; the retrovirus acts as a vector for the new DNA.
Retrovirus-mediated transgenics
-the technique is limited to the size of the transgene and the virus’ own genetic sequence that could interfere with the process.
Retrovirus-mediated transgenics
introduces the transgene DNA at the earliest possible stage of development of the zygote; no vector is needed because the gene is directly injected, therefore no external genetic sequence can interfere with the process.
Pronuclear microinjection
ESC method steps
- ES cells are harvested from the inner cell mass of blastocysts nad are mixed with rDNA
- some ES cells absorbs the DNA and transformed by the new genetic material
- transformed cells will be injected to the inncer cell mass of a host blastocyst
uses ____ proteins to attach DNA to sperm cells; when it fertilizes the egg, the sperm carries the valuable gene along with it.
linker, Sperm-mediated transfer
in animals, it is used to deliver vaccines into
the body.
gene guns
the process of genetically muting the expression of a gene.
knockout
A ________, refers to the use of genetic engineering to inactivate or remove one or more specific genes from an
organism.
knockout
the process of inserting a new gene to the organism
Knock-in or Gene Knock-in
