Transgenic animals, Methods of production and Application of transgenic animals

1. TRANSGENIC ANIMALS

2. CONTENT
⁕Transgenic Animals
⁕Methods of production of Transgenic Animals
⁕Applications of Transgenic Animals
⁕References
2

3. ⁎ Organisms containing integrated sequences of cloned
DNA (transgenes), transferred using techniques of
genetic engineering are called Transgenic Animals.
⁎ Transgenesis is a radically new technology for altering
the characteristics of animals by introducing the foreign genetic material.
⁎ Genetically modified animals are proving ever more vital in the
development of new treatments and cures for many serious diseases.
3
TRANSGENIC ANIMALS (Singhal et al, 2010)
https://www.the-scientist.com/news-opinion/mouse-genomes-
catalogued-41940

4. ⁎ First transgenic animal- SUPERMOUSE was created in 1982.
⁎ It was created by inserting a human growth hormone gene in mouse
genome.
⁎ The offspring was much larger than the parents.
4
https://plantcellbiology.masters.grkraj.org/html/Genetic_Engineering7B-Application-Animal_Biotechnology.htm

5. 5
1. A desired characteristic of offspring could be established in one generation.
2. The characteristic required can be chosen with greater specificity and accuracy.
1. Insertion of foreign gene may upset the expression of the genome.
2. Normal reproduction may result in a transgene being released to the wild population.
BENEFITS
RISKS

6. 6
Methods for Production of Transgenic Animals(Screening Methods in
Pharmacology, 5th EDITION)
DNA Microinjection Method
Embryonic Stem Cell-mediated Gene
Transfer
Retrovirus-mediated Gene Transfer

7. 7
⁎ DNA microinjection method involves the introduction of transgene DNA
directly into the zygote at an early stage of the development.
⁎ No vectors are required.

8. 8
1.
• Isolation of desired genes.
2.
• Cloning of DNA into a vector as a plasmid.
3.
• Female animal is super ovulated by administering FSH and hCG
hormones through intravenous route.
4.
• Super ovulated females are mated with male and then sacrificed.
5.
• After 12 hrs of fertilization, fertilized oocytes are flushed from oviduct
in a form of droplet in a petridish.
6.
• Transgenic DNA is physically microinjected into the pronucleus of a
fertilized egg.
PROCEDURE

9. 9
7.
• The injected embryos are subsequently transferred into the
oviducts of pseudo pregnant female animal.
8.
• Transgenic pups
https://www.biotecharticles.com/Biotech-Research-Article/Genetic-Transformation-Using-Microinjection-2993.html

10. 10
DNA Microinjection (Nishu et al, 2020)

11. 11
⁎ This method involves prior insertion of the desired DNA sequence in
in-vitro culture of embryonic stem (ES) cells.
⁎ The blastocyst (inner layer of a fertilized egg) is harvested and mixed with
recombinant DNA and inserted back in the host’s embryo.
⁎ Transgenic lines are established by mating the progeny that carry the
transgene in the germ line.

12. 12
(Nishu et al, 2020)

13. 13
⁎ This is the method of choice for gene inactivation so it is also called
“Knock-out” method.
⁎ In this method, specific gene can be targeted for disruption by the
incorporation of DNA sequence, usually a selective marker gene into its
coding region.
⁎ Knock-out animals are used as a model system to study the molecular
pathology of human disease, to determine the development and
physiological consequences of inactivating a particular gene.

14. 14
⁎ Gene transfer is mediated by means of a carrier or vector, generally a virus
or a plasmid.
⁎ Retroviruses are commonly used as vectors.
⁎ Normally killed virus has replication defective, so the virus gene is
replaced with the desired transgene.
⁎ The transgene is delivered to the host cell by transfection, it can be used to
transfect a wide range of cells.

15. 15
Anson et al, 2001

16. APPLICATIONS
OF TRANSGENIC
ANIMALS (Nishu et al, 2020)
Disease
Models
Drug and
Industrial
Production
Biological
Models
As
Xenotransp
-lanters
16

17. Transgenic animals as Biological models
• Modification is done to over-express NR2B receptors in
synaptic pathways- to learn fast like juveniles throughout their
lives.
• Can provide information on human development, learning and
memory.
THE SMART MOUSE
• Developed by microinjection of growth hormone into fertilized
eggs.
• To study the effect of growth hormone, accelerated animal
growth, gigantism, correcting genetic defects related to the
growth pattern of animals and humans.
SUPER MOUSE
• Overexpresses urokinase-type plasminogen activator-helpful in
dissolving blood clots.
• Smaller, eat-less and live about 20% longer than normal
species.
• For studying development processes and aging-related to diet.
YOUTH MOUSE
17

18. Transgenic animals as Disease models
# Produced by replacing normal gene with tumor promotor gene.
# For the study of preventing and curing multiple forms of cancer.
# Produced by overexpressing a mutation causing an onset of Alzheimer’s disease by
overproducing proteins that forms amyloid plaques.
# For the study of preventing and curing Alzheimer’s disease.
# Produced by the mutation of the α-synuclein gene- loss of motion control and loss of
dopamine.
#To study the early-onset resulting in earlier diagnosis and treatment of Parkinson’s
disease.
18
ONCOMOUSE
ALZHEIMER’S
MOUSE
PARKINSON’S
FLY

19. Transgenic animals as Xenotransplanters
⁎ Organ transplantation is necessary in those cases when the whole self-organ
fails to function.
⁎ Generally, a small percentage of donated organs are found to be
histocompatible with any patient, and such matched organs are in extremely
short supply.
⁎ Xenotransplanters are animals engineered not to express those antigens that are
recognized by the host immune system responsible for graft rejection.
19

20. ⁎ The only animal currently chosen for xenotransplant research is the pig
because its physiology closely matches that of humans.
⁎ In the pig, a sugar called alpha-1,3 galactosyltransferase present on the surface
of the cells needed to be knocked out.
20
https://www.fda.gov/vaccines-blood-biologics/xenotransplantation

21. Transgenic animals for drug and industrial production (Mohan et al, 2017)
⁎ Transgenic animals are used as bioreactors in the pharmaceutical industry from
protein production to the modification of tissues and organs for transplantation.
⁎ The first human therapeutic protein, antithrombin III was derived in 2006 from
the milk of genetically engineered goats.
⁎ Transgenic animals are used for production of proteins such as alpha-1-
antitrypsin, produced in liver, used in treatment of emphysema or cystic fibrosis.
⁎ This process is less expensive than production of protein through culture of
human cells. 21

22. ⁕ Singhal M, Kansara N. Transgenic animals: production and application. International Journal of
Pharmaceutical Sciences and Research. 2010 Sep 1;1(9):12-22.
⁕ Parmar NS, Prakash S. Screening methods in pharmacology. Alpha Science International Limited; 2006.
⁕ Liu C, Xie W, Gui C, Du Y. Pronuclear microinjection and oviduct transfer procedures for transgenic
mouse production. In Lipoproteins and Cardiovascular Disease 2013 (pp. 217-232). Humana Press,
Totowa, NJ.
⁕ Gupta V, Sengupta M, Prakash J, Tripathy BC. Transgenic Animals and Plants. In Basic and Applied
Aspects of Biotechnology 2017 (pp. 103-123). Springer, Singapore.
⁕ Anson DS. Retroviral-mediated gene transduction. Genomics Protocols. 2001:471-94.
⁕ Rao AS, Lakshmi NB, Medhi B, Prakash A. Pharmacological screening methods and toxicology; 2014.
⁕ Nishu N, Masih S, Kamal S, Jain P, Khan ZK. Transgenic animals in research and industry. In Animal
Biotechnology 2020 Jan 1 (pp. 463-480). Academic Press.
⁕ Mohan G, Kumar S, Deginal R, Prasad K, Kumar A. ADVANCES IN TRANSGENIC ANIMAL
PRODUCTION AND APPLICATIONS. 22
REFERENCE

23. THANK YOU