Transgenic Animals- Animal in which new or altered gene have been experimentally inserted into their genome by genetic engineering technique.

1. Transgenic Animals
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Mr. Dnyaneshwar B Gutale
Master In Pharmacology

2. content
• Introduction
• Method of production
• Transgenic animal used in human disease
• Some example of transgenic animal
• Precaution in transgenic animal
• Advantages
• Disadvanges
• Application
• Recent advancement
• Reference
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3. INTRODUCTION
Definition: Transgenic animal can be defined as animal in which
new or altered genes have been experimentally inserted into their
genome by genetic engineering techniques.
Transgenesis is the process by which mixing up of genes takes
place.
Transgenic technology has led to the development of fishes,live
stock and other animals with altered genetic profile which are
useful to mankind.
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4. First transgenic animal was a ‘supermouse’ created by Ralph
Brinster and Richard Palmiter in 1982.
It was created by insreting a RAT growth hormone gene in mouse
genome.
Mouse-common transgenic experiment animal.
Other animal include pig ,goat, cow, sheep ,fish etc.
Continue……
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5. METHOD 0F APPLICATION
1. Retroviral vector method
2. Microinjecion method
3. Embryonic stem cell method
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6. RETROVIRAL VECTOR METHOD
• The transfer of small pieces of DNA
can be effectively carried out by
retrovirusres
• This method however,is unsuitable for
transfer of large genes.
• Even for small genes, there is a risk of
losing some regulatory sequence.
• Biggest drawback is the risk of
retroviral contamination in the
product obtained from transgenic
animal.
Fig 1:slideshear.net 6

7. MICROINJECTION METHOD
The young virgin female mice are subjected to superovulation.the
superovulated mouse produces 30-35 egg.
The above female mice are mated with male and scarified on the
following day.the fertilized egg are removed from the fallopian tube
Microinjection needle and a holding pipette, the DNA is injected
into the male pronucleus of the fertilized egg.
The eggs with transgenes are kept overnight in an incubator to a
2-cell stage.these eggs are then implanted microsurgically into a
foster mother.
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8. Fig 2: biologydiscussion.com 8

9. LIMITATIONS OF MICROINJECTION METHOD
1. Costly.
2. Skilled personal required.
3. More useful for animal for manipulation.
4. Embryonic cells preferred for manipulation.
5. Knowledge of mating timing ,oocyte recovery is essential.
6. Method is useful for protoplast and not the walled cells.
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10. • The amount of DNA delivered per cell is not limited by the
technique & can be optimised.
• The delivery is precise again increasing the chance of integrative
transformation.
• The small structures can be injected contating only a few cells
&with high regeneration potential.
• It is a direct physical approach, it is host range independent.
ADVANTAGES
DISADVANTAGES
• Injection can cause damage that affects embryonic survival &
can result in quite high mortalities.
• Only one cell is targeted per injection.
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11. EMBRYONIC STEM CELL METHOD
• ES cells are harvested from the inner cell mass of mouse
blastocysts.
• They grown in culture & retain their full potential to produce all
the cells of the mature animal, including its gametes.
• This technology involves the introduction of a foreign DNA ES
cell.
• Foreign DNA can be introduced into ES cells by electroporation
or microinjection.
• Engineered cells with transgene can be identified using marker
gene or PCR analysis.
• Transfected cells can be cultured introduced into blastocyst &
then implanted into foster mother.
• By this way transgenic founder mice are produced.
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13. TRANSGENIC ANIMAL USED IN HUMAN DISEASE
A. Sickle cell disease
B. Amyotrophic lateral sclerosis
C. Chronic hypertension
D. Osteogenesis imperfecta
E. Cystic fibrosis
F. Mitochondrial cardiomyopathy
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14. SOME EXAMPLE OF
TRANSGENIC ANIMAL
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15. TRANSGENIC FISH
Superfish
 Increased growth and size.
 Growth hormone gene inserted into
fertilized egg.
 Transgenic salmon grows about 10-11
times faster than normal fish.
Glo fish
 GM freshwater zebra fish.
 Produced by integrating a fluorescent.
protein gene from jelly into embryo or fish.
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16. TRANSGENIC MOUSE
Alzheimer’s mouse
 In the brain of Alzheimer’s patient, dead
nerve cells are entangled in patient called
amyloid .
 Mouse made by introducing amyloid
precursor gene into fertilised egg of mice.
Oncomouse
 Mouse model to study cancer.
 Made by inserting activated oncogenes.
Smart mouse
 Biological model engineered to overexpress
NR2B receptor in the synaptic pathway.
 This makes the mice learn faster like juveniles
throughout their lives.
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17. TRANSGENIC PIG
Enviro pig
 Pigs have trouble fully digesting a compound known as
phytate found in many cereal grain used to feed them.
 Transgenic pigs are created by introducing phytate
gene of E.coli.
 Phytate enzyme is thus produced in the salivary gland
of pig
 It degrade indigestible phytate with the release of
phosphate that is readily digested by pigs.
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18. TRANSGENIC RABBIT
 Alba, the EGFP (Enhanced Green
Fluorescent Protein) bunny
 Created in 2000 as a transgenic artwork
TRANSGENIC MONKEY
 ANDi was the first transgenic monkey ,born in 2000.
 “ANDi” stands for “inserted DNA” spelled backward.
 An engineered virus was used to insert the harmless gene for
green fluorescence protein (GFP) into ANDi’s rhesus genome.
 ANDi proves that transgenic primates can be created and can
express a foreign gene delivered into their genome.
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19. PRECAUTION IN TRANSGENIC ANIMAL
Working with rodents or rabbits:
 Development of allergies to these species is probably the most
common health hazard.
 Limiting exposure to soiled bedding &the use of gloves & mask
may help.
Working with dogs and cats:
 The risk of transmitted disease is high.
 Toxoplasma is an infectious agent primarily in cat faeces.
Working with sheep:
 Contagious ecthyma from the mouth of an infected sheep can be
transmitted to human causing focal skin lesion on the hands.
 Gloves, masks, and protective cloths.
 Infected person Q vaccine are avaliable.
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20. ADVANTAGES
 Gene requires certain cellular mechanism to help production of
protein.
 Expression through cell culture or bacterial culture requires
constant monitoring & sample.
 Benefits for animal production & health.
 Organ & tissue donation.
 Advance in studies of animal & human disease ,such as cancer.
 Drug production.
 It is more cost effective
 Benefits agriculture & industries ,by being more profitable.
 Transgenic is not only for animal ,also for plant can be applied to
plant.
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21. DISADVANTAGES
 Leads to mutations & functional disorders.
 A new disease could be created.
 Generation of transgenic animal are also expensive.
 High mortality rate.
 Large number of recipient is required for embryo transfer
because of low transgenic rate.
 Live animal are used, so it is essential to do an ethical
examination.
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22. APPLICATION
Medical :
• Disease model
• Bioreactor for pharmaceutical
• Xenotransplantation
Agricultural:
• Disease resistant animal
• For improving quality & quantity of milk , meat, eggs , & wool
production
Industrial importance:
• Toxicity sensitive transgenic animal to test chemical
• Spider silk in milk of goat
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23. RECENT ADVANCEMENT
 Germline stem cell technique:
1. Spermatogonial stem cell technique
2. Primordial germ cell technique
 Gene targeting:
1. Embryonic stem cell gene targeting
2. Somatic cell gene targeting
3. Conditional gene targeting
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