This document discusses transgenic animals. It defines transgenic animals as those with foreign genes deliberately inserted into their genomes. It describes the three main methods for creating transgenic animals: retrovirus-mediated gene transfer, DNA microinjection, and embryonic stem cell-mediated gene transfer. Examples are given of transgenic animals created for medical, agricultural, and industrial purposes, such as disease-resistant livestock, bioreactors that produce useful proteins, and fish engineered for rapid growth. Both the promises and ethical concerns of transgenic technology are acknowledged.

1. BY,
SRI RANJANI TALLAM,
LECTURER IN ZOOLOGY,
D.K(A)GOVT COLLEGE FOR WOMEN,
NELLORE.
04/11/2017

2.  A transgenic animal is one that carries a foreign gene
that has been deliberately inserted into its genome.
 Transgenesis is the process by which mixing up of
genes takes place.
 Foreign genes are inserted into the germ line of
the animal, so it can be transmitted to the progeny.
 Transgenic technology has led to the development of
fishes, live stock and other animals with altered
genetic profiles which are useful to mankind.

3.  First transgenic animal was a ‘Supermouse’ created by
Ralph Brinster (U Pennsylvania) and Richard
Palmiter (University of Washington) in 1982.
 It was created by inserting a RAT growth
hormone gene in mouse genome.
 The offspring was much larger than the parents.
 Mouse – common transgenic expt animal.
 Other animals include pig, goat, cow, sheep, fish etc.

4. METHODS OF GENE
TRANSFER
Retrovirus-mediated gene transfer
 DNA Microinjection Method
Embryonic stem cell-mediated
gene transfer

5. RETROVIRAL MEDIATED GENE TRANSFER

6. DNA Microinjection Method

7. .

8.  Transgenic animals can be created by manipulating
embryonic stem cells.
 ES cells are obtained from the inner cell mass of a blastocyst.
 Transgene is incorporated into the ES cell by
◦ Microinjection
◦ By a retro virus
◦ By electroporation
 Transgenic stem cells are grown in vitro.
 Then they are inserted into a blastocyst and implanted into
a host’s uterus to grow normally.

9. EMBRYONIC STEM CELL METHOD

12.  Medical importance
◦ Disease model
◦ Bioreactors for pharmaceuticals
◦ Xenotransplantation


Agricultural importance
◦ Disease resistant animals
◦ For improving quality and quantity of milk, meat, eggs and
wool production
Industrial importance
◦ Toxicity sensitive transgenic animals to test chemicals.
◦ Spider silk in milk of goat

13. Proteins expressed in Transgenic Animals

15.  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
(Danio rerio)
◦ Produce by integrating a
fluorescent protein gene from
jelly fish into embryo of fish.

16. Alzheimer’s mouse
◦ In the brain of Alzheimer’s patients, dead
nerve cells are entangled in a protein called
amyloid.
◦ Mouse made by introducing amyloid precursor
gene into fertilized egg of mice.
◦ Useful in understanding pathological
basis of the disease.
 Oncomouse
◦ Mouse model to study cancer
◦ Made by inserting activated oncogenes.
 Knockout mice
• Loss of function of specific gene(Gene knockout).
• serve as animal models to study human abnormalities.

17. Growth Differences between Transgenic and Non Transgenic Fish

18.  Enviro pig
◦ Pigs have trouble fully digesting a
compound known as phytate found in many cereal grains
used to feed them.
◦ Transgenic pigs are created by introducing phytase
gene of E.coli.
◦ Phytase enzyme is thus produced in the salvary gland of pig
◦ It degrades indigestible phytate with the release of
phosphate that is readily digested by pigs.
 Pig for organ transplant
◦ Pigs with human genes, in order to decrease the chance of
organ rejection by human body.

19.  Bioreactors whose cells have been engineered to
synthesis marketable proteins.
 More economical than producing desired protein in cell culture.
4/21/201804/11/2017
 Transgenic cattle
◦ Transgenic cows are made to produce proteins lactoferrin
and interferons in their milk.
◦ Prion free cows resistant to mad cow disease.


Transgenic sheep
◦ For good quality wool production.
CYSTEINE TRANSGENE
Transgenic goat
◦ Goats that could express tissue plasminogen
activator, anti thrombin III, spider silk etc in milk.

20.  Alba, the EGFP (Enhanced Green
Flurescent protein) bunny
 Created in 2000 as a transgenic artwork.
 ANDi was the first transgenic monkey, born in 2000.
 “ANDi” stands for “inserted DNA” spelled backwards.
 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.

21.  Blurring the lines between species by creating
transgenic combinations.
 There may be health risks associated with transgenics.
 There may be long term effects on the environment
when transgenic animals are released into the field.
 Various bioethicist argue that it is wrong to create animals
that would suffer as a result of genetic alteration.

22.  Transgenic technology is a field that is under constant evolution.
 Many transgenic animals have been successfully created for
a variety of purposes, and the prospects are enormous.
 It holds great potential in many fields including
agriculture, medicine and industry.
 With proper research and careful use the transgenic animals
can go a long way in solving several problems for which science
doesn’t have a solution till now.

23. THANK YOU